Dot Net Technologies -- MS Tech talk and more

Tip of the Day: Creating a control that displays multiple types of messages using the IValidator interface

Daryl — Tue, 10 Aug 2010 05:06:51 GMT

Today's tip is more than a tip. It's a full project which contains a sample of a control I call the MessageCenter. When developing interactive applications, it's important to provide the user convenient feedback in a consistent location. In my current application I am working on, there are three types of messages (which are typical for most applications) -- errors, informational messages, and warnings.

I wanted to make sure each one appeared different enough so the user could quickly determine which ones needed the most attention. There are a lot of ways I could have accomplished this, such as a class/collection which maintained the type of message, and each class has it's own CSS for displaying. However, I opted for a siumpler solution which is available to every ASP.Net page -- The Validators collection (part of the page object).

The Validators collection maintains a list of objects which implement the IValidator interface. This collection is automatically bound to the ValidationSummary control on the page before (for client-side validation) and after a postback. During a postback for example, you can add a new error to the Page.Validators collection by calling the Add method, and supply a class which implements the IValidator interface.

In the sample project, I implemented three classes -- ValidationError, ValidationNotification and ValidationWarning -- to specify my three different types of messages. Each implements the IValidator interface essentially the same way. I can use the ErrorMessage property of the interface to display the message I want to convey to the end user.

In my page base class, I implemented members to easily add these messages to the Page.Validators collection, as shown below:

 public void DisplayError(string message)
{ this.Validators.Add(new ValidationError(message));
} public void DisplayError(string message, params string[]
p) { DisplayError(String.Format(message, p)); } public void DisplayMessage(string message)
{ this.Validators.Add(new NotificationValidator(message));
}

Note in some of the methods, I can pass in a list of parameters, so I can format the message displayed with a variety of details.

The MessageCenter.ascx control is where the work is done. When added to a page, it provides a ValidationSummary control to handle the clientside validation, and a Repeater which handles the postback messages. With some work, you could integrate the two, but that is way beyond what I needed.

During the Page_Load event of the MessageCenter control, I bind the Page.Validators collection to the Repeater. I also remove these from Page.Validators collection afterwards, as I don't want them displaying in the ValidationSummary control I use for client validation.

 protected void Page_Load(object sender,
EventArgs e) { rptNotification.DataSource = this.Page.Validators;
rptNotification.DataBind(); rptNotification.Visible = (this.Page.Validators.Count
!= 0); for (int idx = (this.Page.Validators.Count - 1);
idx >= 0; idx--) { IValidator val = this.Page.Validators[idx]; this.Page.Validators.Remove(val);
} }

During the ItemDataBound event of the repeater, I determine the type of IValidator, and set the appropriate image to the row of data. I bind the IValidator class ErrorMessage property to the label inside the repeater row as well, and set the appropriate CSS class so it displays in the color format I like.

protected void rptNotification_ItemDataBound(object sender,
RepeaterItemEventArgs e) { try { if ((e.Item.ItemType
== ListItemType.Item) || ((e.Item.ItemType == ListItemType.AlternatingItem))) { IValidator
val = Page.Validators[e.Item.ItemIndex];
Image img = (Image)e.Item.FindControl("imgNotice"); if (img
!= null)
{ if (val is NotificationValidator)
img.ImageUrl = "~/images/info.png"; if (val is ValidationError)
img.ImageUrl = "~/images/error.png"; if (val is ValidationWarning)
img.ImageUrl = "~/images/warning.png";
} Label lblInfo = (Label)e.Item.FindControl("lblDetails"); if (lblInfo
!= null)
{ lblInfo.Text = val.ErrorMessage; if (val is NotificationValidator)
lblInfo.CssClass = "NotificationItem"; if (val is ValidationError)
lblInfo.CssClass = "ErrorItem"; if (val is ValidationWarning)
lblInfo.CssClass = "WarningItem";
} } } catch (Exception
ex) { //TODO:
Log the error } } }

The end result is a control which sits on top of the page (and is only visible when there are messages to display) and looks like this:

Notification[1].zip (38.27 KB)

UPDATE: Had a bug in the original file, so I updated the project (and cleaned out all the ancillary junk in it as well) and posted it again.

Tip of the Day: The evolution of dynamic, case insensitive LINQ to Object search

Daryl — Mon, 09 Aug 2010 04:34:12 GMT

I designed a control to filter data dynamically, and I wanted to be able to be able to use it to filter either SQL Data (via a DataTable) or a List<T> of objects. Sorting the DataTable dynamically is easy using the DataTable, as you can create a DataView and perform case insensitive searches like this:

DataView
dvData = new DataView(data);
dvData.RowFilter = “SomeField=’Test’”;

You can also create widcard searches like this:

DataView
dvData = new DataView(data);
dvData.RowFilter = “SomeField
LIKE ’Te%’”;

But providing that functionality with List<T> and LINQ was going to be a challenge. If you know the properties you want to find in advance, the syntax is easy using Lambda functions:

List<MyObject>
objectResults = MyList.FindAdd(x
=> x.MyProperty.ToLower() == “Value”);

That’s well and good, but in my filter control, I wanted to be able to specify a property by name for a comparison. Something like this:

List<MyObject>
objectResults = MyList.FindAdd(x
=> “MyPropertyName” == “Value”);

Unfortunately, that’s not going to work. I needed something that would dynamically specify the property I want to search. In a previous post I described how I could use a defined Lambda Expression to dynamically sort a list in a similar fashion.

So in my first attempt and doing a lot of searching on Google, I came up with this method:

 public static IEnumerable<T>
DynamicFilter<T>(this IEnumerable<T>
source, string propertyOrFieldName, string searchValue)
{ Func<T, bool>
predicate = CreatePredicate<T>(propertyOrFieldName,
searchValue); return source.Where(predicate);
} static Func<T, bool>
CreatePredicate<T>(string propertyOrFieldName, string searchValue)
{ var arg = Expression.Parameter(typeof(T), "arg");
var body = Expression.Equal(Expression.Property(arg,
propertyOrFieldName), Expression.Constant(searchValue)); return Expression.Lambda<Func<T, bool>>(body,
arg).Compile(); }

Usage:

List<Employee>
emps = Employee.LoadListCollection();
List<Employee> empList = emps.DynamicFilter("FirstName", "Angie").ToList();

This worked great for a case-sensitive search, but I still didn’t have a way to do a case-insensitve search or a wildcard search. So after some more searching and more trial-and-error, I came up with this for a wildcard search:

public static IEnumerable<T>
ContainsString<T>(this IEnumerable<T>
data, string propertyOrFieldName, string searchValue)
{ var param = Expression.Parameter(typeof(T), "x");
var body = Expression.Call( typeof(BusinessObjectBase).GetMethod("Like",
BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.Public),
Expression.PropertyOrField(param, propertyOrFieldName), Expression.Constant(searchValue, typeof(string)));
var lambda = Expression.Lambda<Func<T, bool>>(body,
param); return data.Where(lambda.Compile());
}

A couple things to note here. First, I needed to add a method “Like” to my base object (BusinessObjectBase in this case) of the collections I am searching. It looks like this:

///
<summary> ///
comparison operator. Needed for dynamically filtering the objects ///
</summary> ///
<param name="a">A.</param> ///
<param name="b">The b.</param> ///
<returns></returns> static bool Like(string a, string b)
{ return a.ToLower().Contains(b.ToLower());
}

Now I can do a search where I specify the property name, and it returns and value of that property that contains any part of that string (and it is also case-insensitive).

List<Employee>
emps = Employee.LoadListCollection();
List<Employee> empList = emps.ContainsString("FirstName", "An").ToList();

Then it occurred to me that I was specifying the name of the static routine in the call. What would happen if I specified the name of the operator dynamically? Would it work right?

var
body = Expression.Call( typeof(BusinessObjectBase).GetMethod("Like",
BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.Public), 


Became this:




var
body = Expression.Call( typeof(BusinessObjectBase).GetMethod(operatorName,
BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.Public), 
Now
I could create two static operators (or as many as I might ever need) to provide this
dynamic functionality.



public static IEnumerable<T>
RunOperator<T>(this IEnumerable<T>
data, string operatorName, string propertyOrFieldName, string searchValue)
{ var param = Expression.Parameter(typeof(T), "x");
var body = Expression.Call( typeof(BusinessObjectBase).GetMethod(operatorName,
BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.Public),
Expression.PropertyOrField(param, propertyOrFieldName), Expression.Constant(searchValue, typeof(string)));
var lambda = Expression.Lambda<Func<T, bool>>(body,
param); return data.Where(lambda.Compile());
} In my BusinessObjectBase class, I added the following methods (Like
for wildcard searches, and Equals for a case-insensitive search):

 static bool Like(string a, string b)
{ return a.ToLower().Contains(b.ToLower());
} static bool Equals(string a, string b)
{ return a.ToLower()
== b.ToLower(); } 
I can call both of these methods like this:

public List<T>
FilterData<T>(List<T> data, bool wildcardSearch)
{ List<T> results = data; if (wildcardSearch)
results = results.RunOperator("Like",
fi.DataField, fi.FilterValue()).ToList(); else     results = results.RunOperator("Equals",
fi.DataField, fi.FilterValue()).ToList();     return results;
} So let’s break it down a little. First, the first parameter of a lambda
expression, which is what we are building here, is the input parameter, or in this
case, the x portion of x =>.

var
param = Expression.Parameter(typeof(T), "x");Next,
we’re setting up the call which is made to the right of the => of the Lambda expression.
The code below is saying “grab the method name provided by the operatorName variable,
which can be found in any class which implements the BusinessObjectBase class.



typeof(BusinessObjectBase).GetMethod(operatorName,


The result of the expression defined above will be returning a boolean, as defined
here:

var
lambda = Expression.Lambda<Func<T, bool>>(body,
param);Finally, we return the data which evaluates in the lambda expression
as true via this line of code:



return data.Where(lambda.Compile());Note
the delegate lambda expression is compiled into executrable code and produces a delegate
which represents the lambda expression.

Obviously, understanding how to dynamically call methods and compare properties using
LINQ is extremely powerful and has many,many possibilities. I hope this helps someone
else trying to do the same thing!

Tip of the Day: An extension method to HTML encode a string

Daryl — Thu, 05 Aug 2010 01:39:30 GMT

Ever need to HTML Encode a string? This useful extension method will do it for you:

 ///
<summary> ///
Extension method to HTML encode any string characters with ASCII > 127 ///
</summary> ///
<param name="str">string to be encoded</param> ///
<returns>Encoded string</returns> public static string ToHtml(this string str)
{ return string.Join("",
str.ToCharArray().Select(c => (int)c
> 127 ? "&#" + (int)c + ";" :
c.ToString()).ToArray()); }

Tip of the Day: T-SQL Script to rename bulk columns

Daryl — Wed, 04 Aug 2010 04:22:15 GMT

The project I am currently working on is a port from a horribly over-engineered Oracle system to a much more manageable SQL Server system. One of the things we needed to do was rename a lot of fields to something more usable. For instance, every table had a field titled "Ended" but we felt it was easier to think of that record as "Deleted". Rather than go through every table (and it wasn't in every table, meaning you needed to manually check each one to verify), I opted a scripting solution.

Below is a T-SQL script which will generate the sp_rename scripts for all the tables where the target field is found. A job which would have taken hours and been prone to errors is now a simple task taking a minute.

DECLARE @OldFieldName VARCHAR(50),
@NewFieldName VARCHAR(50) SET @OldFieldName
= 'SomeOldFieldName' SET @NewFieldName
= 'MyNewFieldName' select 'sp_RENAME
' + CHAR(39)
+ 'OFC.' +
TABLE_NAME + '.' +
@OldFieldName + CHAR(39)
+ ',
' + CHAR(39)
+ @NewFieldName + CHAR(39)
+ ',' + CHAR(39)
+ 'COLUMN' + CHAR(39)
+ CHAR(10)
+ 'GO' + CHAR(10) from INFORMATION_SCHEMA.COLUMNS WHERE COLUMN_NAME
= @OldFieldName ORDER BY TABLE_NAME

The script above will generate the T-SQL code to rename any field SomeOldFieldName to MyNewFieldName. Run it, and then run the generated script.

Given this and CodeSmith, can you tell I enjoy scripting work?

Tip of the Day: CodeSmith - Retrieve the unique columns from a table

Daryl — Tue, 03 Aug 2010 05:13:07 GMT

Today I was setting up a new template, and I needed to look at the unique constraints as part of my task.

The following CodeSmith script will load the columns that have unique constraints (but not the primary key) into an ArrayList.

 ArrayList
uniqueColumns = new ArrayList(); for (int i = 0;
i < SourceTable.Indexes.Count; i++) { if (SourceTable.Indexes[i].IsUnique)
{ for (int y=0;
y < SourceTable.Indexes[i].MemberColumns.Count; y++) { if (!SourceTable.Indexes[i].MemberColumns[y].IsPrimaryKeyMember)
uniqueColumns.Add(SourceTable.Indexes[i].MemberColumns[y].Name); } } }

Upgraded das Blog and Hosts

Daryl — Wed, 28 Jul 2010 18:58:20 GMT

Recently, my shared hosting provider decided to "upgrade" their system, and in the process it pretty much decimated my web sites. I managed to get content back up, but nothing much works, and I just haven't had time to rectify that, starting with switching hosts. I have slowly started migrating things to the new host, and last night finally got around to upgrading das Blog and moving that site over. There were a few glitches, but my new host resolved them fairly quickly, and now I can start taking care of my backlog of posts I have earmarked for writing about.

It's been a busy few months, and the biggest achievement has been cashing at the WSOP this year. I almost did it twice even!

Now it's time to focus on the business and my technical skills again. The nice thing is that I finally got around to setting it up to allow me to blog from email, which makes it a LOT more convenient to post things, as I always have email handy. A lot has been going on, and some of the things I need to update:

Updating content from my main business site, Rubicon Computing Solutions, LLC (still need to migrate it so I can update the content)
Technical ScreeningsPossible technical interviewing skills seminar (working with a local recruiting firm to help put something together)
Tips of the Day
New tools and links which are cool (so need to get the Rubicon site working again to post these)

I am hoping this weekend I can make the time to get these moving again. So welcome to the updated blog!

Tip of the Day: More useful information on INFORMATION_SCHEMA

Thu, 11 Mar 2010 04:02:00 GMT

Recently, I posted a script which would identify all the procedures which did not have appropriate permissions set, which is great for last minute deployment checks. I realized I needed to explore INFORMATION_SCHEMA closer as there is a LOT of useful metadata about the database available. Today's tip is about some of that useful information.

INFORMATION_SCHEMA is a specia schema which contains several views of the database metadata. Previous to these views, database developers were forced to join on several sys tables. Many of my earlier scripts for example rely on this method. However, in SQL Server 2005 system views were provided which made this task significantly easier. Here's some of the more useful views to look at. Explore them with code like this and see what they contain.

SELECT * FROM INFORMATION_SCHEMA.COLUMNS

I have found the following most useful, although in truth I suspect over time I will have use for all of them.

COLUMNS --> I frequently use this to find what tables a particular column name is found in

CONSTRAINT_COLUMN_USAGE --> identify what keys (primary, foreign) are defined, and on what fields

ROUTINES --> allows me to explore procedures and functions using this view

TABLES --> Get information about the various tables in the database

VIEW_COLUMN_USAGE --> obtain information on the fields the view contains

Here's a good link where you can find more information on the INFORMATION_SCHEMA.

Opinion: Giving your employees some love (or else!)

Wed, 10 Mar 2010 03:18:49 GMT

As I was walking around today, I noticed one of the managers had a book about employee retention and it really struck home with me. This particular book, at least from the title, looked to be about retaining key people (and a follow up search in Amazon verified this) with “love”.

Way back in early 2000’s, we had this thing called the “dot-com boom” followed up by the “dot-com bust”. I say way back because so much has changed in the last 10 years, a lot of people may have forgotten how development has changed in that time. The market went from people making exorbitant hourly wages and stock options to a dramatic shift of struggling to even find a job. I was very fortunate as a contractor as I took less than a 10% rate cut and didn’t have one day of bench time.

Most of the other independent contractors weren’t that fortunate. Many took catastrophic pay cuts which dramatically altered their lifestyles. Others left IT altogether. The developer market was insane during the “dot-com boom”, so in my opinion it needed a correction.

On the flip side, I saw employers taking advantage of the situation. In one example, a friend of mine gave up contracting, and took a contract-to-hire position. After the end of three months, he was scheduled to hire at a certain wage. He worked his contract, but when it came time to hire him, they revised his offer to about $10,000 less than the original offer. It wasn’t a performance issue, and they bluntly told him that. When they revised the offer, they advised him they made the change because the market was poor, and they knew it would be difficult for him to find another job.

The manager who did this and I had a decent relationship, and I pulled him aside to discuss it. He verified they were changing the original offer on all offers which had not been completed “because they could”. My warning to him was that, while his reason is correct, the market would eventually change, and those same people would be the first to leave. Time proved me correct.

I am a student of history. One of my favorite quotes is as follows:

"Those who cannot remember the past are condemned to repeat it." -- George Santayana

Fly forward 10 years, and again we have a market with developers struggling to find jobs, having to take large pay cuts, and management taking advantage of it. Last year, I was the development manager for a large financial institution with a decent sized team. We had a huge conversion going on, and we had to convert 58 applications in six months. Since a lot of the applications were forward facing, we could afford no errors. Fortunately, I had the right team to do it.

Through incredible dedication our team was successful. During this conversion, I began to notice a disturbing trend from senior management. It began by demanding reports of hours spent working by individual employees. No attention was paid to *what* they were working on or the results of their efforts, but rather how much they were working. It was interesting to note that contract employees were not pressured about their hours, as their hours were all billable.

Fortunately, I am very results driven. After my team submitted their reports, I “adjusted” their reported time (note: this was not used for ANYTHING other than to see who is working and who was not – I wrote the application that did this reporting) so it would keep the team in good graces. My philosophy has proved to work every time à do your job, do it on time, and do it with quality. If it takes you 80 hours to do it, so be it, but I will make sure you are taken care of. If you can do it in 40, all the better. I know in Extreme programming they hold it to 8 hours maximum per day, but I was never a huge advocate of XP.

The trend with senior management continued, and they began monitoring network traffic. Management now wanted reports, by department and employee, of where employees were going on the internet and how long they spent there. I met daily with the other IT managers, and I was the only manager who openly opposed this. The main reason they remained silent was because they had access to the logs and could “filter” the reports to senior management. Senior management’s stated belief is that every minute spent on the web was one minute lost of productivity. Don't even get me started on the studies which disprove this.

Their original strategy was going to block all internet activity (except senior management). When I pointed out basic points like looking for code and solutions on the internet was critical to development, this movement lost steam. However, that’s when the reports started. I knew my time was limited there when I received my inquisition about my team's activites à one employee had watched CNN from his laptop at 9 PM (while working from home) and another had paid his bills online (after working an 80+ hour week).

These same managers would call all the employees in to tell them there would be no raises, a decrease in benefits and reduced time off. Granted, the institution was taking some charge-offs on loans, but from an accounting standpoint, the merit increases would not have impacted the balance sheets significantly compared to other expenditures being made. In the same meetings, they’d press for more hours of productivity (regardless of status of their projects). In every case, the team was told “the market out there is rough. If you don’t like it here, go ahead and look, you won’t find anything.”

My department successfully completed the conversion with few problems, none of them critical. Fortunately, I saw things were getting worse, and I left that company for another immediately after the conversion, feeling I had met my obligation to my employer as well as my team. I stay in touch, and I hear my team was singled out in a post-conversion "pep rally". The team had been working 70+ hours on average for over six months for the conversion, probably more than any other team, and most projects were complete and things had slowed down. A senior manager told my old team directly: “If you’re not working 65 hours every week, you’re not pulling your weight. I can hire replacements for you right now at 70% of your salaries.”

I wish that kind of attitude was isolated. The next company I went to had a worse attitude towards employees. On my first day as their new development manager, I was told by their very inexperienced VP of Technology “it’s good to fire people here and there to keep the others on their toes. It’s healthy.” Although there is some distant truth to that statement, it’s also dangerous and naïve as well.

The point of all this background is that history is going to repeat itself. Take the financial company I mentioned. Even in this economy, several key people have already left. Many others have openly stated they will leave as soon as they can.

The book I first mentioned had it right: if you want to keep your employees, you need to show them your love. Regardless of the economy, your key team members will stay as there is more to work than just salary. If you lose a GOOD employee, you stand to lose a lot. For example:

· Cohesion of the team

· Legacy knowledge that only time and experience can bring

· Coding standards – you can have these written, but it takes time and reviews to “train” employees on how things should be done. They leave, you lose this.

· Investment – good employers invert in their team. This can include training, goodwill or any of a number of tangible and intangible investments made on the team. When you lose a team member, you lose that investment.

· Loyalty & trust

Sure you can hire new developers, but finding good ones is an art. Will you be improving by replacing your current team? There is certainly a cost associated with it.

It’s not all about salary either. Many times I didn’t have the budget to pay my team what I felt they were worth or even what they could get on the open market. I kept them happy by allowing them the ability to create innovative solutions, be part of the “bigger direction” of the team, and keeping their skills current as the technology changed. All this is part of the “love” a good manager can easily give his team.

After the first “dot-com bust” resolved itself, that first employer I mentioned lost 100% of their team over the first year the economy recovered. I am afraid history will be repeating itself just as harsh this time.

Tip of the Day: Locating scripts without execute permissions set

Fri, 05 Mar 2010 04:36:29 GMT

Creating a script to grant execute to stored procedures where none exist

It’s very common to forget to script out permissions for a stored procedure when generating the script. There’s nothing more frustrating than deploying some code changes, only to have them not work because you have elevated security on your development SQL Server, but not on QA or Production. If you find one, likely you’ll find it several places. How do you quickly locate the procedures which don’t have the desired permission set? Better yet, how do you fix it quickly without writing a lot of script or manually setting the permissions in SQL Server Management Studio?

The script below is one I pulled off the internet (http://sqlfool.com/story/46/date-posted/06-06-0939/) and modified a little. Since the environment I am in now uses multiple schemas, I added the ability to specify schema to search for.

Here’s the script:

DECLARE @role VARCHAR(50)
DECLARE @targetSchema VARCHAR(50)
SET @targetSchema = 'dbo'
SET @role = 'MyUser'

SELECT 'GRANT EXECUTE ON ' + SPECIFIC_SCHEMA + '.[' + SPECIFIC_NAME + '] TO ' + @role + CHAR(10) + 'GO'
FROM INFORMATION_SCHEMA.ROUTINES WITH (NoLock)
WHERE SPECIFIC_NAME Not In
(SELECT o.name FROM sys.database_permissions p WITH (NoLock)
INNER Join sys.objects o WITH (NoLock)
ON p.major_id = o.OBJECT_ID
INNER Join sys.database_principals u WITH (NoLock)
ON u.principal_id = p.grantee_principal_id
WHERE u.name = @role)
AND ROUTINE_TYPE = 'PROCEDURE'
AND SPECIFIC_NAME not like 'sp_%'
AND SPECIFIC_SCHEMA = @targetSchema
ORDER BY SPECIFIC_NAME

Just change the @targetSchema and @role variables and run it. The results will be a list of procedures on the current database which don’t have execute permissions assigned to the indicated @role. You can then copy those procs you want to grant execute on into the query window and execute them.

Tip of the Day: Manipulating ASP.Net validators client side

Tue, 02 Mar 2010 04:29:40 GMT

This tip will show how to get a reference to a validator using client-side script, check the valid state of the validator control, and set a validator control active state client-side as well.

I ran across a situation today to validate two dates (txtStartDate, txtEndDate) with the following criteria:

txtStartDate is required (use RequiredFieldValidator)
txtEndDate is required (use RequiredFieldValidator)
txtStartDate must be a valid date (use RegularExpressionValidator)
txtEndDate must be a valid date (use RegularExpressionValidator)
txtStartDate must occur before txtEndDate (use CompareValidator)

Granted, I could write client script for doing this in one fell swoop, but I inherited this page and these validators were already there, and I was just there to fix a bug.

The QA person logged an issue like this:

txtStateDate value – 11/1/2009

txtEndDate value – 11/31/2009 (invalid date)

The “bug” was that in this case txtEndDate is not a valid date. The RegularExpression Validator correctly caught this, but the Compare Validator still fired, indicating a second error. The QA person felt that we should only display an “invalid date” error.

My options were to strip out the RegularExpressionValidator and CompareValidator and use a CustomValidator and write some javascript. But really all I needed to do is disable the CompareValidator if the txtBeginDate or txtEndDate is not a valid date.

It took some doing, but I came up with a simple solution. I added a CustomValidator, and called a client side function called ControlEndDateValidators(). You need one for each date input.

<asp:CustomValidator ID="valEndDateCheck" runat="server" ControlToValidate="txEndDate" ClientValidationFunction="ControlEndDateValidators" />

The function obtains a reference to the validators, and the compare validator is only made active if the data is valid per the RegularExpressionValidators. To check and see if a validator is valid client-side, check the isvalid property for true/false.

function ControlEndDateValidators(source, arguments)

{

var regExpValidatorEndDate = document.getElementById("<%=valEndDate.ClientID %>");

var regExpValidatorBeginDate = document.getElementById("<%=valStartDate.ClientID %>");

var compareValidator = document.getElementById("<%=valDate.ClientID %>");

ValidationEnable(compareValidator, (regExpValidatorBeginDate.isvalid) && (regExpValidatorEndDate.isvalid));

}

function ValidationEnable(val, enable)

{

val.enabled = (enable != false);

ValidatorValidate(val);

ValidatorUpdateIsValid();

}

</script>

Again, we could write client-script code perform all this validation, but sometimes time is of the essence. Using the functions above, we have shown how to get a reference to a validator client-side, check whether it is valid, and finally enable a validator on the client-side.

Tip of the Day: How to register class based user controls in a web project

Wed, 06 Jan 2010 03:52:06 GMT

The latest project I am working on is a web site project, which differs significantly from a web application project. If you need a little background on the difference, here's some links:

http://www.codersbarn.com/post/2008/06/ASPNET-Web-Site-versus-Web-Application-Project.aspx

http://reddnet.net/code/aspnet-web-site-vs-web-application/

We wanted to create some base controls, such as for the GridView so that common functionality could be consistant across the web site. It's simple to create a user control to do this (e.g. an .ascx file), but in this case we wanted to do it as a class.

In the web application, that's no problem because we know what the assembly name is. In a web site template, we don't, so how do we register the control for use? It took a few minutes of digging around and trying a few things, but I finally got it, and I decided to share it for the next person looking.

Let's say I define my base GridView class like this:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI.WebControls;

namespace BaseControls
{
/// <summary>
/// Summary description for BaseGrid
/// </summary>
public class BaseGrid : GridView
{
   public BaseGrid()
   {
      //
      // TODO: Add constructor logic here
      //
   }

   public string SomeMethod(string someString)
   {
      return someString;
   }

}
}

Note the namespace. By default the web project may not have it, so you'll need to create one.

In order to reference it on the page, you'll actually leave the assembly blank. Your register tag will look something like this:

<%@ Register Namespace="BaseControls" TagPrefix="wf" %>

Now, to use the control, all you need to do is put this on the aspx page.

<wf:BaseGridID="grdReport"runat="server"Width="95%"…. (use it like a normal GridView)

In code, you can then use the properties/methods like this:

grdReport.SomeMethod("test");

Tip of the Day: Dynamically sorting a List collection using Lambda.Expression

Wed, 30 Dec 2009 04:58:02 GMT

In the past week, I created some CodeSmith templates for my client so we could quickly generate the business objects for our web site. Since the project will be VS2008, I decided to bing objects to List<T> collections of objects, so I could start leveraging LINQ to Objects in the code.

They wanted every field in the GridView sortable, and I always looks for an reusable way to do things when possible. Since we were going to have many, many grids, this was a great opportunity to use generics and LINQ to come up with a flexible solution.

In this case, I wanted a way of taking in a field name, and sort direction, and sorting the collection. It was easy to do using a Lambda expression if I knew in advance all the field names, such as MyCollection.OrderBy(a => a.Name) to sort by name. Obviously, that wasn't going to work. I needed to create a delegate for sorting on the right field dynamically.

Below is the result of that effort. By using the Lambda.Expression (provided by System.Core.dll), I was able to dynamically set the Lambda expression to the property I wanted. Depending on the direction, I used OrderBy or OrderByDescending with the dynamic sort expression. I created it as an extension method to all List<T> objects for quick and easy access, which every business object in my solution supports.

/// <summary>
/// Sorts a list of objects by passing in the parameter and direction.
/// Usage: List<MyObject> newList = oldList.SortList("SomeColumn", "SomeDirection");
/// Requires System.Core be included in the project.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="list">The list.</param>
/// <param name="sortColumn">The sort column.</param>
/// <param name="direction">The direction.</param>
/// <returns></returns>
public static List<T> SortList<T>(this List<T> list, string sortColumn, string direction)
{
var param = Expression.Parameter(typeof(AutoClassParams), sortColumn);
var sortExpression = Expression.Lambda<Func<T, object>>(Expression.Convert(Expression.Property(param, sortColumn), typeof(object)), param);

List<T> newList = null;

if (direction.ToUpper() == "ASC")
newList = list.AsQueryable<T>().OrderBy(sortExpression).ToList<T>();
else
newList = list.AsQueryable<T>().OrderByDescending(sortExpression).ToList<T>();

return newList;
}

Tip of the Day: Eliminating unused "using" statements and sorting them

Tue, 29 Dec 2009 04:43:28 GMT

I am a big fan of Resharper, but right now I am at a client who doesn't use it. Today, I accidentally reset my toolbar, so I was going through and adding my settings (yes, I could have restored an old one..)

As I was doing it, I ran across two items I relied on Resharper to handle.

One will remove unused "using" statements, and the other will sort them in your class by namespace.

Here's what they look like:

They can be found in the Edit Menu items.

Tip of the Day: SSIS -- adding carriage returns to annotations

Wed, 11 Nov 2009 17:13:49 GMT

It's been a LONG time since I did any SSIS work, and I really enjoy it. I'm writing an ETL process for importing general ledger transactions, and it's a fairly complex task. To help notate what needs to be done as well as explain some of the complexities, I am making sure to annotate the code in the Control Flow.

I had forgotten how to add carriage returns in annotations, so this is more a reminder again just in case I forget: Ctrl-Enter will do the trick!

New features of VS2010 which have me smiling (Part 2)

Sat, 07 Nov 2009 03:45:19 GMT

Session compression – For out-of-process session maintenance, the session state is compressed using the System.IO.Compression.GZipStream class. It also looks like it will only do this when CPU cycles are available (but I need to investigate this further). If that’s the case, you might want to set up some Performance indicators or alerts when it’s not being compressed because that might indicate further problems.

Link: <http://www.asp.net/learn/whitepapers/aspnet4/default.aspx>

Multi-Targeting – I’ve mentioned this before, but it allows you to specify which .Net version you are writing for in the VS2010 IDE. This expands the support that VS2008 has by adaptively changing the IDE to the targeted environment. The IDE adjusts its Intellisense and compilation towards the targeted version. The whitepaper indicates ASP.Net, so I need to test and see if it applies to WPF and WinForm as well. Some features:

Specified in the .config file, defaults to 4.0 when not specified.
Compiles the code to the
Intellisense adapts to the current version of the framework selected

Link: <http://www.asp.net/learn/whitepapers/aspnet4/default.aspx>

Link: http://weblogs.asp.net/scottgu/archive/2009/08/27/multi-targeting-support-vs-2010-and-net-4-series.aspx

Script Loading – The AJAX library includes the ability to have better control of script loading in .Net 4.0. It loads the scripts automatically, and in the order needed. From the whitepaper, here’s the features:

· Automatically loads all resources that are required by a script.

· Makes sure that each script is loaded only once.

· Improves performance by loading scripts in parallel and by combining scripts.

· Supports loading scripts only when they are needed (“lazy loading”).

· Supports loading third-party scripts like jQuery and your own scripts.

· Supports loading scripts from the Microsoft Ajax Content Delivery Network

One of the client features is the Sys.require. When a component and a function is provided, the callback function is called when the scripts are done loading.

Link: <http://www.asp.net/learn/whitepapers/aspnet4/default.aspx>

jQuery integration – Speaking of jQuery, it’s now included as part of the ASP.Net Web forms and the MVC project.

Link: <http://www.asp.net/learn/whitepapers/aspnet4/default.aspx>

ClientID changes – I am mixed about this one, simply because once In understood how ASP.Net set its clientIDs upon rendering, I could generate my script accordingly in my code behind. However, it’s been simplified in VS2010 to allow the user to have control over setting the client IDs. Be forewarned though, this could open you up to naming issues within container controls as such. Regardless, I am always supportive of giving the developer the option of more control. There’s a new property at the configuration file, page and control level called ClientIDMode which has the following settings:

AutoID – mimics the previous version naming scheme
Static – This specifies that the ClientID value will be the same as the ID without concatenating the IDs of parent naming containers.
Predictable – useful for controls which will be generated in template controls
Inherit – take the setting of the parent control (lots of this in VS2010, which is great, since I have been a champion for UI inheritance and control-centric programming).

Link: <http://www.asp.net/learn/whitepapers/aspnet4/default.aspx>

Improved “Add Reference” functionality – Over the past couple of days, I found myself converting a project from VS2005 to VS2008. As a result, I found myself needing to change some references as well as I changed some of the related projects. This change in VS2008 is sort of a “nice to have”. While it’s not a big win, it’s still nice as it can get painful at times changing the references. Here are the changes with this:

The .Net and COM tabs are loaded asynchronously
Defaults opening to the project tab (I find myself using this a LOT anyways, but would have preferred this to start at the “Browse” tab, or better, consider this like a MRU action and remember where I was last time)

Link: <http://weblogs.asp.net/scottgu/archive/2009/10/29/add-reference-dialog-improvements-vs-2010-and-net-4-0-series.aspx>

UML Support! Visual Studio 2010 will support the creation of UML diagrams via a modeling project. I like Visio and all, but I look forward to being able to create UML diagrams right from the same IDE I develop in. As of now, there’s no code generation support. I do think a clever developer could possible do some code generation from the saved file via CodeSmith or IDE programming, so I bet we’ll see something like that soon if Microsoft doesn’t provide it first. Check out the link below and you can see some of the functionality.

Link: http://weblogs.asp.net/gunnarpeipman/archive/2009/11/04/visual-studio-2010-uml-modeling-projects.aspx

Although available in v3.5, VS2010/v4 will have the chart control integrated into it. In the past, your options were a third-party control for charting or to use Interop and Excel, or writing your own charting libraries (gulp!). The link below lists some details on this impressive charting library if you’ve never used it.

Link: http://weblogs.asp.net/scottgu/archive/2008/11/24/new-asp-net-charting-control-lt-asp-chart-runat-quot-server-quot-gt.aspx

Developers will have more deployment options Web application

Get it here: http://msdn.microsoft.com/en-us/vstudio/dd582936.aspx

Tip of the Day: Marking old routines obsolete

Fri, 06 Nov 2009 03:43:11 GMT

There comes a time when old code needs to be laid to rest. For example, as I migrate applications to VS2008, I find myself converting common functions to extension methods where it makes sense to take advantage of the new language functionality. Lately, I have been doing this a LOT. I don’t want to have to maintain separate libraries for each version, but I am also not doing much development in older versions of .Net either.

Fortunately, .Net provides us with the ability to make old code obsolete. We have two options with this:

Make it so users can still use the functionality, but inform them new functionality exists
Require them to use the new functionality

There is an attribute called “System.Obsolete” which allows us this option. It can be used on a most anything (classes, properties, functions, structs, etc), and has the following syntac in C#:

[System.Obsolete(“Some description – provide the new recommended way”, true/false)]

The true/false (defaults to false) parameter indicates if you want to create a compilation error if this method is used. I do wonder about the usefulness of this paramter though, as at that point, why not make sure it’s in source control and delete it? I guess for historical purposes it might make sense to keep it.

 
    public class TestClass

    {

        [System.Obsolete("Use
NewMethod()")]

        public void OriginalMethodStillAvailable()

        {

            //Do
Something...

        }

        [System.Obsolete("Use
NewMethod()", true)]

        public void OriginalMethodNotAvailable()

        {

            //Do
Something...

        }

        public void NewMethod()

        {

            //Do
Something...

        }

    }

If you try to use the method which is marked obsolete, but
allowed, you'll see something like this:

If you try to use one with the obsolete flag set to true, you'll see a compilation error like this:

New features of VS2010 which have me smiling (Part 1)

Sat, 31 Oct 2009 04:22:38 GMT

As I mentioned before, I historically have avoided beta software. However, this time I am breaking that rule and really digging into VS2010 early. Below are a few of the things which have me very excited to see this release (and with Web Spark, I get it for free! Join now!) This is part one of a multi-part entry of the things I find really appealing about the upcoming version of Visual Studio 2010.

IntelliTrace – allows you to playback and trace a session to assist with debugging. The major features are:

Application Event Recording
Playback Debugging (a.k.a Time Travel Debugging)
Record and Playback of Manual Test Failures
Debugging Build Acceptance Tests
Diagnosing Unit Test Defects
Debugging Load Test Failures

Link: http://blogs.msdn.com/habibh/archive/2009/06/02/an-in-depth-look-at-the-historical-debugger-in-visual-studio-2010-part-i.aspx

Auto-Start applications – Helps mitigate large startup processes which may run during the web application “Application_Start” event. Provides a controlled approach for starting up the application.

Link: http://weblogs.asp.net/scottgu/archive/2009/09/15/auto-start-asp-net-applications-vs-2010-and-net-4-0-series.aspx

Better ViewState management – By default, ViewState is enabled for web controls in past versions of ASP.Net. In VS2010, ViewState can be disabled by default and onlt enabled for those that actually need it, and it now supports “inheritance” through the ViewStateMode property. This allows you to set it to “Inherit” the value from the parent control.

Link: http://www.asp.net/learn/whitepapers/aspnet4/

Outut Caching everywhere -- Now you can take advantage of caching in applications other than web based, as the cache API is exposed without using the System.Web.Cache in a WinForm application. There are also more providers, and the ability to create your own through extensibility.

Link: http://www.asp.net/learn/whitepapers/aspnet4/

Reduced web.config size – Most of the configuration settings have been moved to the machine.config file, which greatly simplifies the configuration settings in the web.config file.

Link: http://www.asp.net/learn/whitepapers/aspnet4/

Get the VS2010 Beta 2 here: http://msdn.microsoft.com/en-us/vstudio/dd582936.aspx

Tip of the Day: Using generics to simplify getting a value from a DataRow or DataReader

Fri, 30 Oct 2009 04:17:54 GMT

Once you have data loaded into a DataRow or SqlDataReader, you’d typically do something like this:

string someValue = (string)drData["MyValue"];

In order to place it in the variable, you need to cast the
type correctly (in this example, using the(string)). Also, what happens if “MyValue”
is null?  You’ll need to do an additional check, and then assign the value you
want for the situations where it is null.

Today’s tip uses generics to return the correct type. It
also allows you to return a default value if the value is null. 

        /// <summary>

        /// Gets
the data row value.

        /// </summary>

        /// <typeparam
name="T"></typeparam>

        /// <param
name="valueName">Name of the value.</param>

        /// <param
name="drData">The dr data.</param>

        /// <param
name="defaultValue">The default value. Note,
this must be cast to the expected return type. For example, decimal.Parse("0").</param>

        /// <returns></returns>

        protected T
GetDataRowValue<T>(string valueName, DataRow drData,
T defaultValue)

        {

            if (drData[valueName]
== DBNull.Value)

                return defaultValue;

            else

                return (T)drData[valueName];

        }

        /// <summary>

        /// Gets
the data row value.

        /// </summary>

        /// <typeparam
name="T"></typeparam>

        /// <param
name="valueName">Name of the value.</param>

        /// <param
name="drData">The dr data.</param>

        /// <param
name="defaultValue">The default value. Note,
this must be cast to the expected return type. For example, decimal.Parse("0").</param>

        /// <returns></returns>

        protected T
GetDataRowValue<T>(string valueName, SqlDataReader drData,
T defaultValue)

        {

            if (drData[valueName]
== DBNull.Value)

                return defaultValue;

            else

                return (T)drData[valueName];

        }

Here’s
how it’s used. Notice that through the use of generics, one routine can handle multiple
types. 
 

            int myID
= GetDataRowValue("SomeID", drData, 0);

            DateTime myDate
= GetDataRowValue("SomeDate", drData, DateTime.Now);

            decimal myAmt
= GetDataRowValue("SomeDecimalAmount", drData, decimal.Parse("0"));

            string myString
= GetDataRowValue("SomeString", drData, String.Empty);

Tip of the day: Opening a process and (optionally) waiting

Thu, 29 Oct 2009 04:12:31 GMT

Every once in a while, you need to open another application from your WinForm application. Today’s snippet is a wrapper which will give you the ability to start a new process (application). It takes two parameters:
filename – string - the name full path of the application to open
waitToFinish – bool - True/False – setting to true will cause your program to stop until the opened application finishes processing.

        private static void OpenApplication(string fileName, bool waitToFinish)

        {

            OpenApplication(fileName, String.Empty,
waitToFinish);

        }

        private static void OpenApplication(string fileName, string arguments, bool waitToFinish)

        {

            using (System.Diagnostics.Process prc
= new System.Diagnostics.Process())

            {

                prc.StartInfo.FileName
= fileName;

                if (arguments.Trim().Length
> 0)

prc.StartInfo.Arguments = arguments;

                prc.Start();

                if (waitToFinish)

                {

prc.WaitForExit();

prc.Close();

                }

            }

        }

To use them, here’s an example usage:

        private void button1_Click(object sender, EventArgs e)

        {

            OpenApplication(@"c:\windows\notepad.exe", false);

            MessageBox.Show("Alert
that processing has continued!", "Processing..", MessageBoxButtons.OK, MessageBoxIcon.Information);

        }

Tip of the day: Validate string meets length requirements

Wed, 28 Oct 2009 04:09:54 GMT

This routine checks the specified minimum and maximum string lengths, and either returns True/False that it meets those requirements, or could also throw an exception (based on the throwException parameter value).

This would also be a good candidate for an extension method. To do so, add a parameter (in the first position) as “this string”.

        /// <summary>

        /// Checks
the length of a string to see if it meets the minimum and maximum length

        /// </summary>

        /// <param
name="checkString">string to check</param>

        /// <param
name="minLength">minimum string length</param>

        /// <param
name="maxLength">maximum string length</param>

        /// <param
name="stringName">description of the value to
check</param>

        /// <param
name="throwException">T/F to throw an exception
if it exceeds the maximum</param>

        /// <returns>T/F</returns>

        public static bool ValidString(string checkString, int minLength, int maxLength, string stringName, bool throwException)

        {

            if ((checkString.Length
>= minLength) && (checkString.Length <= maxLength))

                return true;

            else

            {

                if (checkString.Length
< minLength)

                    if (throwException)

    throw new System.ArgumentOutOfRangeException("The
argument string - " + stringName + " was less
than the minimum length.");

                    else

    return false;

                if (checkString.Length
> maxLength)

                    if (throwException)

    throw new System.ArgumentOutOfRangeException("The
length (" + checkString.Length.ToString() + ")
of argument string - " + stringName + " was longer
than the expected length(" + maxLength.ToString() + ").");

                    else

    return false;

                return false;

            }

        }

Tip of the Day: Winform: Displaying the form derived from a base class

Wed, 14 Oct 2009 05:27:16 GMT

When starting a project, I always recommend inheriting objects from a base object, regardless of whether you know you'll need it or not. Usually, they will contain common functionality like error handling, debugging or other common methods which you'll use over and over.

In WinForms, however, this can cause a problem if you make the base form an abstract class (another thing I recommend). For example, take this simple form:

Now let's say I decide to derive this form from an abstract base class, which I will call BaseForm:

    5 using System.Windows.Forms;

    6 

    7 namespace TestForm

    8 {

    9     public abstract class BaseForm : Form

   10     {

   11         protected void SomeCommonMethod()

   12        
{

   13 

   14        
}

   15     }

   16 }

When I go to edit the UI again, I see this, and it scares
the heck out of me (looks scarier in VS2005)....

What this is telling you is that it can't render an abstract class BaseForm. So while you are creating the application, you might remove the abstract identifier from UI related base classes (with a note that they should be inherited from, not used, as well as a /TODO marker to make sure you mark it as abstract before deployment).

Doing this will allow you to inherit from a base class while at the same time edit the UI.

Employment screenings and coaching

Wed, 07 Oct 2009 04:14:00 GMT

Been quiet on the blogging front because I finally have clients for my "side" work. I haven't even put it on my site yet, but I have been working with a contracting firm to help screen candidates with technical interviews so they can place them in interviews at the appropriate positions. It's been interesting, and so far the candidates have been very strong. Strong enough that if I was a development manager again, I would have hired them in a second.

In my last position where I was interviewing and hiring, I was surprised at how poor some of the candidates were. Part of it was the method the company was using to locate candidates. I understand they were trying to save money, but when it comes to quality people, you can't skimp. One thing I will tell any developer is make sure you establish good relationships with recruiters. Yes, it takes some effort, but it can reap benefits when it comes to a job search or even in learning about unlisted jobs, or the environments there. As they get to know you, good recruiters will match you to the environments where you will thrive. I am amazed when developers complain that recruiters only want to close the sale. While this is true of some, as a developer, you have a responsibility of establishing the relationship with the recruiter so they look for your interests. You'll quickly learn which recruiters they are.

I also have my first interview coaching session coming up. One of these nights I am going to get this information up on the Rubicon Computing site, but for now, it's all been word of mouth and careful marketing to recruiters and developers I know. I have a nice AJAXified information request form, but I need to work on some of the verbiage first.

At some point things will slow down enough to put some more tips up. I have been developing a list of them to write, so likely it will be a lot at once!

Tip of the Day: Directly accessing a Master Page

Tue, 29 Sep 2009 04:34:35 GMT

When using master pages, there are times when you want to access part of the Master Page (e.g. a public property). One way of doing this is by defining the master page with the MasterType directive.

<%@ MasterType VirtualPath="~/MyMasterPage.master"%>

By doing this, you can now access the MasterPage as a class Master, and programatically (and with the benefits of compilation checking) access it.

Catching up is hard to do...

Tue, 29 Sep 2009 04:23:27 GMT

So much is going on, where to begin. First, I'll start with WebSpark. I've had my issues with Microsoft programs in the past, but this one does make up some ground. First, I'll lead you to the place where I first heard of the program, Scott Guthrie's site.

The gist of the program is if you are a small company (less than 10 developers) and you are designing web sites for other companies, they'll give you development software for 3 years for $100 (and server software). If you decide to keep it, you'll pay $999, and even that is a bargain. You get upgrades (hint --> VS2010) as well. This is a huge deal with a very easy qualification.

On a personal front, I was bidding on some things on eBay, and needed to pay for them via PayPal. I haven't used either in years, primarily in that I got taken on eBay, and PayPal refused to help on my dispute. The advised me that they hoped I used my credit card so I can dispute that, as they were unable to help. Doesn't PayPal prefer our checking accounts?

The issue came about because I ordered a very expensive GPS system which had near realtime traffic updates. The listing described the GPS as in "mint, like new" condition (the words from the ad). The problem was, the seller decided to make a little extra money and sell the traffic antenna (costs $200 to replace) and not mention that in their description of "mint". When I contacted PayPal to dispute the issue (after the seller told me I was screwed), they were not helpful and refused my claim agreeing with the seller. Apparently mint does not mean complete. Never again. Score one more victory (lost customer) for foreign customer service! I say that because the emails had some of the worst English I have ever seen. Ever. I should dig them out and post them kind of bad.

But alas, there are certain things you can only find on eBay, and PayPal is the only way to pay sometimes. I signed up for my account, and connected my credit card to it this time. However, as part of their verification process, they process a $1.95 charge, then you have to enter the code. At the bottom is a disclaimer, which seemed written by a 5 year old. To paraphrase, it went something like this:

"If you contact your credit card company to get this transaction information, and your credit card company complains to PayPal, your account may be cancelled." -- Nice...

Tip of the Day: Redirecting page trace output to a file

Fri, 25 Sep 2009 05:11:05 GMT

If you'd like to redirect your page trace infomation to a file (which can be useful when you are trying to run down a problem and don't want the world to see your trace information during testing), it's as simple as this:

Add this to your web.config:

< trace enabled="true" traceMode="SortByTime" pageOutput="false" localOnly="false" />>

The key is the pageOutput="false" which tells the framework to redirect the trace info to the trace.axd file. To view the trace information, you just need to load the page in the browser, such as:

http://localhost:4774/trace.axd

This will allow you to see the trace history of any browsed files since the trace was started, as well as clearing the trace history. Just remember to remove this before you deploy (or make sure you compile in release mode!).

Interviewing Question of the Day: Virtual Keyword

Wed, 23 Sep 2009 04:45:06 GMT

It's time I got back to the interviewing tips as well. So here's an OOP question a suprising number of candidates miss:

Question: In C#, what's the virtual keywork used for.

Answer: A method marked virtual has an implementation, but inheriting objects may override the implementation and provide their own implementation. This differs from the abstract keyword in that the base class does not have an implementation, and the deriving class must provide an implementation.

This is a key concept to object-oriented programming. If you missed this one, you can get more information on Microsoft's MSDN site.

Tip of the day: More WinForm tooltip tips...

Wed, 23 Sep 2009 03:58:23 GMT

So I made a lot of progress on my WinForm application today, and I ran across an issue where I was displaying two tooltips for the same control. I probably would never usually have noticed it, but in this case, I was dynamically setting the contents of the tooltips, and the length of the first tip (which was underneath) was substantially less than the length of the topmost tip.

In debugging the problem, I was looking for a method to clear all previous tooltips associated to the control. I found one (but didn't seem to work), but also noticed a plethora of other cool functionality available to me. Some of the neat properties:

IsBalloon --> Set to true, creates a balloon style tooltip

ToolTipTitle --> A string you can use create a "title" for your tool tip.

ToolTipIcon --> A constant which shows an appropriate icon to the left of the title/tooltip

BackColor --> allows you to set the background color of the tip

There are many more, but I have changed my tooltip routine to look like this:

        public static void SetToolTip(System.Windows.Forms.Control ctrl, string description)

        {

            System.Windows.Forms.ToolTip tt
= new System.Windows.Forms.ToolTip();

            tt.ShowAlways = false;

            tt.IsBalloon = true;

            tt.UseAnimation = true;

            tt.ToolTipTitle = "Info";

            tt.ToolTipIcon = System.Windows.Forms.ToolTipIcon.Info;

            tt.SetToolTip(ctrl, description);

        }

The end result went from this:

To this!

Tip of the Day: WinForms and adding tooltips programmatically

Tue, 22 Sep 2009 04:38:13 GMT

You can always grab the ToolTip control out of the toolbox, but I prefer to add a common function to a base form so I don't have to remember to add this control to the form. Then, any time I want to add a tooltip, I pass in the control and the text, and this simple snippet will take care of it for me. I remembered it as I needed to add some tooltips, which is something the existing application lacks.

        protected void SetToolTip(IContainer component, Control ctrl, string tip)

        {

            try

            {

                ToolTip tooltip
= new ToolTip(component);

                tooltip.SetToolTip(ctrl,
tip);

                tooltip.Active
= true;

            }

            catch

            {

                //Don't
worry

            }

        }

Usage: 

   41 SetToolTip(this.components,
lvwCategories, "Right click for menu options...");

New projects take time

Tue, 22 Sep 2009 04:15:25 GMT

Going to try to make up for some lost time here, as this new project is taking up a good deal of my time. OK, not exactly true initially, as it took a full week to get the access I needed, but now I have my environment set up, and I submitted my Functional Specification Document for the project for review. Technically I am not supposed to begin coding until mid-October, but I don't think the Technical Document will take nearly that long, so I am creating some prototypes in the mean time to foster some discussion of some of the changes I am making.

So I am going to post some WinForm related tips, simply because that's what I have been working. I have a long list of things I wanted to write about though, so who knows what will end up here while I have the energy to do so.

As I review this project, I came across a lot of things I would love to change. For example, everywhere there is data access code, they repeat the same functionality. By encapsulating that code, I could probably reduce the overall lines fo code and complexity considerably. However, I was advised not to, because changing code means more testing, and even with that, if something changed breaks, there will be Hell to pay.

Regardless if I try to take that risk, which I feel is well warranted, I also see lots of opportunities for CodeSmith templates to generate the code. It's not a big project, and it will probably take longer to write all the specifications than it will to actually code, but that's how it goes sometimes.

Useful Link -- Information on shortcut keys in the Visual Studio IDE

Wed, 16 Sep 2009 05:22:12 GMT

Earlier, I posted a useful link at Rubicon Computing Solutions for a poster of all the keyboard shortcuts in the Visual Studio IDE. As I was looking for some more neat shortcuts, I came across this site with more useful tips -- mainly, how to enumerate all the shortcuts, and how to customize them.

I have had many occasions to have to remap the shortcuts, primarily related to add-ons I have placed in my IDE. The macro in the referenced Microsoft link will help show what the current mappings are, which would be extremely useful if you needed to do a lot of remapping.

More VS2010 features -- optional parameters in C#

Wed, 16 Sep 2009 04:36:56 GMT

I am getting settled in my new project, and it only took me a week to get rights to install anything on the laptop! A lot of people would say "Wow, a billable week with no work!" but personally, the days just drag by. I'd much rather be buried in code. I did make some good use of the time though, digging into what documentation I could find and creating a new Functional Specification Document. I did finally get my rights, so tomorrow will be spent installing things and looking into code again.

I did get some reading done though, and I saw that in VS2010 C# will have optional and named parameters. I know the VB crowd (of which I come from) will chuckle a little at that, as that feature has been around forever. Until now, it's required C# developers to overload functions. Nothing Earth-shattering about this feature, other than as part of it, C# will support named parameters and default values as well as part of the implementation (the default values are part of the defiinition of the function).

Tip of the Day: Debugging -- Conditional Breaks

Mon, 07 Sep 2009 22:46:14 GMT

Most people set break points, and iterate through code until they find the condition they were looking for. Although (IMHO) poorly documented, it's possible to place a condition on your breakpoint to have it stop when your condition is met.

Let's look at this code:

   20        
    int maxIdx = 15;

   21        
    for(int idx=1;
idx < maxIdx; idx++)

   22        
    {

   23        
        Response.Write("Index:" +
idx.ToString());

   24        
    }

 

If I were to place a breakpoint on line 23, the debugger
would stop every time it hit the Response.Write. For a small loop that *might* be
ok, but let's say I notice something weird with the 13th item. Within the breakpoint
itself, I can place a condition when I actually want it to stop, in this case, the
13th iteration.

 

By right clicking on the debug "circle", the following context-sensitive
menu comes up: 

 

Select "Condition" and the following dialog appears:

In the textbox, place the condition that you want. In this case, when idx == 13, the condition is true, and therefore, the breakpoint will now be active and execution will stop.

When a condition for a breakpoint is set, you'll notice the image for the breakpoint changes as well:

Tip of the Day: Debugging -- Break on Error

Mon, 07 Sep 2009 22:28:20 GMT

This has been around for quite some time, but I am always suprised when I go to a new client site at the number of developers who don't know how to make the debugger stop when it encounters an error. This is a repeat tip of a long time ago, as it's just that useful. It's a very useful debug trick because some projects are so large, you don't know where to start looking for an issue. Additionally, an error may actually be occurring somewhere unexpected because it's getting caught in error handling.

By setting it to break on "Thrown", the debugger will stop right where an error originates. To turn this functionality on, you can select the "Debug" menu item, and select "Exceptions". For you hot key fans out there, you can invoke the dialog with Ctrl+Alt+E. When you do, you'll see the following dialog. Mark the "Thrown" box for the "Common Language runtime Exceptions" as shown below.

When done debugging, save yourself some grief and uncheck the "Thrown" box, otherwise you'll be stopping a LOT when you don't mean to.

Looking into Microsoft Expression -- A design tool

Sat, 05 Sep 2009 15:55:17 GMT

As I was looking through Scott Hanselman's List of Tools for 2009, I saw a reference for Microsoft's Sketchflow (part of Microsoft Expression), which allows you to design (among other things) and work through ideas prior to coding. I am going to check it out this weekend, and maybe some of the alternate tools he recommended for his post. I might even have to dust off my Table PC, as it seems like a good combination.

Tip of the Day: A brief explanation of extension methods

Fri, 04 Sep 2009 05:10:29 GMT

There’s a very powerful feature in .Net 3.5 called extension methods. In an earlier blog, I used an extension method in my LINQ to XML to format the date retrieved from an RSS feed. If you’re new to the 3.5 framework, you may be wondering what the big deal is.

As a consultant, I have to look at a lot of old and 3^rd party code. There are times when I don’t have access to the source code, and I need to add some additional functionality to a class. If I can inherit from the base class, I can just inherit the class and extend it. But what do I do if the class is sealed? Prior to .et 3.5, my options were limited and certainly not as object oriented. I’d have to write some type of wrapper of common function to create the functionality.

As an example, let’s say I wanted to extend string with some additional functionality, such as adding in functionality to reverse a string easily. I create my new class, and try to inherit from the String class, but I get a compilation error. Let’s look at the definition of the String class in .Net:

[SerializableAttribute]

[ComVisibleAttribute(true)]

public sealed class String : IComparable,

ICloneable, IConvertible, IComparable<string>, IEnumerable<char>,

IEnumerable, IEquatable<string>

Because the class is sealed, I can’t inherit from it. Prior to .Net 3.5, I am going to have to create a function and pass in the string. By using extension methods, I am no longer restricted by the “sealed” keywords.

/// <summary>
/// Reverses the specified string.
/// </summary>
/// <param name="s">The string to reverse.</param>
/// <returns>Reversed string</returns>
public static string Reverse(this string s)
{
   char[] arr = s.ToCharArray();
   Array.Reverse(arr);
   return new string(arr);
}

The code above extends any string with a new Reverse function, which reverses the referenced string. Here’s how it is used:

string testString = "MyString";
string reversedString = testString.Reverse();

The new reverse function shows up in Intellisense for any string, which helps speed up coding as well.

So how did this work? It’s all in the definition. First, the class and the function has to be defined as static. Second, the first parameter must begin with this and is a reference to the type this method extends.

There are some restrictions to static methods. For example, the extension method can only access public methods of the referenced class.

Below are some more examples of extending the string class with some additional functionality. A couple of days ago, I posted some examples of getting values from a DataRow safely. This would be another great refactor opportunity to extend the DataRow class to provide this functionality right from the DataRow itself.

using System;
using System.Globalization;
using System.Text.RegularExpressions;
using System.Threading;

namespace Rubicon.Common
{
public static class StringExtensions
{
/// <summary>
/// Reverses the specified string.
/// </summary>
/// <param name="s">The string to reverse.</param>
/// <returns>Reversed string</returns>
public static string Reverse(this string s)
{
   char[] arr = s.ToCharArray();
   Array.Reverse(arr);
   return new string(arr);
}

/// <summary>
/// Converts the string to title case.
/// </summary>
/// <param name="s">The string to convert.</param>
/// <returns>A title case string.</returns>
public static string ToTitleCase(this string s)
{
   CultureInfo ci = Thread.CurrentThread.CurrentCulture;
   TextInfo ti = ci.TextInfo;
   return ti.ToTitleCase(s);
}

/// <summary>
/// Returns true if string is over the specified max length
/// </summary>
/// <param name="s">The string to check.</param>
/// <param name="maxLength">max length.</param>
/// <returns></returns>
public static bool OverMaxLength(this string s, int maxLength)
{
   return (s.Length <= maxLength);
}

/// <summary>
/// Returns true if string is under the specified min length
/// </summary>
/// <param name="s">The string to check.</param>
/// <param name="minLength">min length</param>
/// <returns></returns>
public static bool UnderMinLength(this string s, int minLength)
{
   return (s.Length <= minLength);
}

/// <summary>
/// Checks the length of the string to make sure it is within the set bounds.
/// </summary>
/// <param name="s">The string to check.</param>
/// <param name="minLength">min length</param>
/// <param name="maxLength">max length</param>
/// <returns></returns>
public static bool WithinValidLength(this string s, int minLength, int maxLength)
{
   return ((s.Length >= minLength) && (s.Length <= maxLength));
}

/// <summary>
/// Determines whether the string is alpahbetic only.
/// </summary>
/// <param name="s">The string to check.</param>
/// <returns>
///     <c>true</c> if [is alpha only] [the specified s]; otherwise, <c>false</c>.
/// </returns>
public static bool IsAlphaOnly(this string s)
{
   Regex regPattern = new Regex("[^a-zA-Z]");
   return !regPattern.IsMatch(s);
}

/// <summary>
/// Determines whether the string is alphanumeric.
/// </summary>
/// <param name="s">The string to check.</param>
/// <returns>
///     <c>true</c> if [is alpha numeric] [the specified s]; otherwise, <c>false</c>.
/// </returns>
public static bool IsAlphaNumeric(this string s)
{
   Regex regPattern = new Regex("[^a-zA-Z0-9]");
   return !regPattern.IsMatch(s);
}

}
}

Extension methods are a very powerful tool, and enhance OOP concepts like encapsulation. They will help you organize your code, and extend the functionality of classes previously you could not modify. I obtained my first taste of Extension Methods in this book as I was learning LINQ, and I highly recommend it.

Starting new projects.. how to approach it?

Thu, 03 Sep 2009 19:41:58 GMT

Next week, I’ll be starting a new project, which is always exciting for me. In this case, it will be a WinForms application, which I really enjoy working on. Since everything is more web-oriented these days, there just aren’t as many WinForms projects. In fact, I haven’t done one in about two years where I built an application for a major phone system manufacturer which takes Oracle data/Excel spreadsheets, imports the data and generates a PDF price list.

I know a lot of people dread deployment of WinForm apps, which is one of many reasons web development has taken off. From my perspective, it’s an even trade because web development has many challenges.. scalability, security, browser compatibility, etc. Mostly, since WinForm apps are so rare these days, it’s going to be a fun contract to do something different for a change.

But that’s not the point of this post. I was thinking about how I approach a new project (in this case, it’s a re-write of an older application) and what I do to get it started.

In this case, it will look something like this:

· Get oriented (passwords, system information, high-level project overview)

· Get the environment set up

· Get a high level view of what the project entails

From there, it’s time to dig in. In this case it’s a re-write, so one of the many questions I ask will be to find out what was lacking or has changed since the first application, and what the new desired features are. Ultimately, this may entail a semi-working prototype. I’ll also want to familiarize myself with how the old application works. This is important, as most people don’t like a lot of change unless it really improves the process, so it’s good to understand how they currently use it, and how they want to use it. You need end user buy-in to be successful, so it’s important that any change you make will be accepted.

So now we get to designing and ultimately coding. It usually involves a few things:

· Architecting the application

· Data Mining/design

· Designing tests

· Deployment Strategy

· Post-deployment support

· Documentation

To architect the application, I need to see if there are any existing architectures in place. Very rarely am I given free reign to build the data access layer, but it does happen. A lot of contractors really push this, or ignore current architectures, but that’s a mistake. I say this because you need to leave an application which your client can support. If I do change the existing practices in place, I make sure I know WHY, communicate it and document it.

Now come the tools. Some clients won’t allow you to bring your own software licenses. In that case, I may have to do a CodeSmith demo to help justify the purchase of the tool. I’ll look for opportunities to generate code and speed up development. I have had a LOT of push back on that from other contractors though, in that they feel you are losing billable time by generating all that code, but I disagree. First, as a consultant, I feel I have a duty to save my client money and time where I can. Second, when you do quality work and it’s fast, I assure you that you’ll be either getting more projects or called back. In my 13 years of consulting, almost every client I have has brought me back for subsequent projects for that exact reason.

I also bring things like my data mining queries in my other blog posts which help find what I need to find quickly.

What tools/techniques do you use?

Tip of the Day: Getting Table Counts

Wed, 02 Sep 2009 17:34:10 GMT

I can't take credit for this, as I took it from the article How To Get Table Row Counts Quickly And Painlessly on SqlServerCentral.com by Kendal Van Dyke. However, it such a good tip, I had to change it a bit, as I tend to use this a LOT.

First, I made the results a little more "printable" but reducing the table name column. Next, I made it a system proc because when I go onto client sites, I am looking at many databases. I probably don't need to create a procedure for it, but there have been many cases where I trend things, and it would be nice to have this handy. Finally, I added a parameter to allow me to change the sorting. By default, it sorts by table name. I added an optional parameter to allow me to pass in an integer (could have done it a million ways, I know, but I chose to do this solely for my preferences -- feel free to change to yours).

Usage: sp_retrieveRowCounts --- sorts by table name

sp_retrieveRowCounts 1 ---sorts by row count, then table name

Here's the proc:

USE master
GO

IF (SELECT OBJECT_ID('sp_retrieveRowCounts','P')) IS NOT NULL
BEGIN
    DROP PROC sp_retrieveRowCounts
END
GO

CREATE PROC sp_retrieveRowCounts (@OrderByCount int = null)
AS
BEGIN

    DECLARE @OrderByParm int
    DECLARE @SQLStatement varchar(700)
    DECLARE @OrderByClause varchar(35)

    SELECT @OrderByParm = ISNULL(@OrderByCount,0)

    IF (@OrderByParm != 0)
        SELECT @OrderByClause = ' ddps.row_count DESC, o.NAME ASC'
    ELSE
        SELECT @OrderByClause = ' o.NAME ASC'

    SELECT @SQLStatement = 'SELECT TableName = LEFT(o.name,50), TotalRows = ddps.row_count FROM sys.indexes AS i
     INNER JOIN sys.objects AS o ON i.OBJECT_ID = o.OBJECT_ID
     INNER JOIN sys.dm_db_partition_stats AS ddps ON i.OBJECT_ID = ddps.OBJECT_ID
     AND i.index_id = ddps.index_id
    WHERE i.index_id < 2
     AND o.is_ms_shipped = 0
    ORDER BY ' + @OrderByClause

    EXEC(@SQLStatement)

END

--Mark procedure as system object
EXEC sys.sp_MS_marksystemobject sp_retrieveRowCounts
GO

GRANT EXEC ON sp_retrieveRowCounts TO public
GO

Tip of the Day: sp_findsp revisted

Tue, 01 Sep 2009 04:20:43 GMT

I posted about sp_findsp previously and decided to revisit it. I didn't write it (see previous post for credit/link) but I did add a bit to it. First, I cleaned it up a bit to make it easier to read, and second, I made it so that it is a system proc so I could access it from any db on my server. I may end up doing some cleanup on it's output, but that's all I had time for for now. So here goes, the new version!

USE master
GO

PRINT 'Checking for the existence of this procedure'
IF (SELECT OBJECT_ID('sp_generate_inserts','P')) IS NOT NULL --means, the procedure already exists
BEGIN
PRINT 'Procedure already exists. So, dropping it'
DROP PROC sp_findsp
END
GO

CREATE PROC sp_findsp @s varchar(255)
AS
BEGIN
    DECLARE @msg varchar(255) ,@ul varchar(255)
    SELECT @s='%' + @s + '%'

    SELECT 'SP Name'=upper(o.name), Seq=colid ,'SP Line'=substring(text,patindex(@s,text)-5, 30)
    FROM syscomments c , sysobjects o
    WHERE o.id=c.id
    and patindex(@s,text) > 0
    ORDER BY [name]

    SELECT @msg='* Stored procedures containing string "' + @s + '=' + convert(varchar(8),@@rowcount) + ' *'

    SELECT @ul=replicate('*',datalength(@msg))
    PRINT ' '
    PRINT @ul
    PRINT @msg
    PRINT @ul
END
GO

--Mark procedure as system object
EXEC sys.sp_MS_marksystemobject sp_findsp
GO

PRINT 'Granting EXECUTE permission on sp_findsp to all users'
GRANT EXEC ON sp_findsp TO public

GO

Tip of the Day: A system procedure for locating fields in a database

Tue, 01 Sep 2009 04:10:15 GMT

When I go onto a client site, I usually don't have the luxury of designing everything from scratch. There are times (like on my current engagement) if I were given the choice, I'd say scrap it, but usually it doesn't happen that way. It is what it is... been saying that a lot lately!

So one of the tools I find useful is the ability to search for particular field names in the database. This is very similar to sp_findsp I use, which I have posted in the past off the net, but I have modified it so it gets registered as a system procedure.

So here's sp_findfields. It will return a fairly printable representation of the results of all fields which match the passed in string. It's registered as a system procedure in this script, so it is accessible to all databases.

Usage:

sp_findfields '%Contact%'

This will find all fields with the string 'Item' in it. Note you need to provide the wildcard characters.

USE master
GO

IF (SELECT OBJECT_ID('sp_findfields','P')) IS NOT NULL
    BEGIN
        DROP PROCEDURE sp_findfields
    END
GO

CREATE PROCEDURE sp_findfields
(@searchText varchar(50))
AS
BEGIN

    SELECT SchemaName = LEFT(TABLE_SCHEMA,10),
        TableName = LEFT(TABLE_NAME, 35),
        FieldName = LEFT(COLUMN_NAME, 40),
        DataType = LEFT(DATA_TYPE, 13),
        DataSize = CHARACTER_MAXIMUM_LENGTH,
        AlloysNulls = IS_NULLABLE
    FROM INFORMATION_SCHEMA.columns
    WHERE column_name like @searchText
    ORDER BY TableName, FieldName
END
GO

--Mark procedure as system object
EXEC sys.sp_MS_marksystemobject sp_findfields
GO

GRANT EXEC ON sp_findfields TO public
GO

Gadgets and more

Mon, 31 Aug 2009 04:26:21 GMT

Since I am going back into full time consulting, I decided lugging around twenty 800 page books is a bad idea. Tonight, I pulled the trigger in a Kindle DX. A bit pricy, but the fact I can annotate my books (and export the annotations) and read native PDFs, I can see the value in the price. I only wish it allowed you to annotate PDFs, as I know I can put a LOT of things in PDF form and place on there.

So I was noticing Amazon charges for placing RSS feeds on the Kindle, and I decided to either find a service which converts RSS feeds to PDF format, or write one myself. Fortunately, I found Tabbloid, which mails your RSS feeds in PDF format at an interval you specify. Even better, it looks free. I may still write one and put some filtering capability in it, but this is a win for now.

The other gadget I have and just enjoy is my Pioneer XMp3 player. It allows me to record XM content, and place all kinds of music on the Micro SD card. It's still kind of buggy, and with the XM-Sirius merger, I don't imagine that will change, but I still enjoy it immensely.

.Net 4.0 Multi-Targeting

Sun, 30 Aug 2009 15:31:31 GMT

Normally, I don't have enough time to really dig into the bleeding edge technologies, but I am trying to rectify that. The question is always "When is it too early.."

For now, I have been looking at some of .Net 4.0's newer features, and one really cool thing for environments which have years of legacy software is called "Multi-targeting". Essentially, it allows you set the target environment for an application in the same IDE (but later target new versions).

As an example, let's say you are currently using ASP.Net 2.0, and you have to because of client concerns. No problem, you'll be able to set the VS IDE to target the 2.0 framework. However, when you decide to upgrade, you can just change the target framework version. The neat thing is that the IDE willl hide and show Intellisense based on the target framework as well.

Scott Guthie is writing a series on it I plan on following closely. This time, I may just have to be more bleeding edge than I have been in the past.

Tip of the Day: Get values from DataRows safely

Sat, 29 Aug 2009 18:32:59 GMT

The following code snippets make retrieving values from DataRows safely, and properly casts them to the desired values.

        /// <summary>

        /// Gets
the int value from data row.

        /// </summary>

        /// <param
name="fieldName">Name of the field.</param>

        /// <param
name="dr">The dr.</param>

        /// <returns></returns>

        public static int GetIntValueFromDataRow(string fieldName, DataRow dr)

        {

            return (dr[fieldName]
== DBNull.Value ? 0 : Convert.ToInt32(dr[fieldName].ToString()));

        }

        /// <summary>

        /// Gets
the int value from data row.

        /// </summary>

        /// <param
name="fieldName">Name of the field.</param>

        /// <param
name="dr">The dr.</param>

        /// <param
name="defaultValue">The default value.</param>

        /// <returns></returns>

        public static int GetIntValueFromDataRow(string fieldName, DataRow dr, int defaultValue)

        {

            return (dr[fieldName]
== DBNull.Value ? defaultValue : Convert.ToInt32(dr[fieldName].ToString()));

        }

        /// <summary>

        /// Gets
the string value from data row.

        /// </summary>

        /// <param
name="fieldName">Name of the field.</param>

        /// <param
name="dr">The dr.</param>

        /// <returns></returns>

        public static string GetStringValueFromDataRow(string fieldName, DataRow dr)

        {

            return (dr[fieldName]
== DBNull.Value ? String.Empty
: dr[fieldName].ToString());

        }

        /// <summary>

        /// Gets
the string value from data row.

        /// </summary>

        /// <param
name="fieldName">Name of the field.</param>

        /// <param
name="dr">The dr.</param>

        /// <param
name="defaultValue">The default value.</param>

        /// <returns></returns>

        public static string GetStringValueFromDataRow(string fieldName, DataRow dr, string defaultValue)

        {

            return (dr[fieldName]
== DBNull.Value ? defaultValue : dr[fieldName].ToString());

        }

        /// <summary>

        /// Gets
the bool value from data row.

        /// </summary>

        /// <param
name="fieldName">Name of the field.</param>

        /// <param
name="dr">The dr.</param>

        /// <returns></returns>

        public static bool GetBoolValueFromDataRow(string fieldName, DataRow dr)

        {

            return (dr[fieldName]
== DBNull.Value ? false : Convert.ToBoolean(dr[fieldName].ToString()));

        }

        /// <summary>

        /// Gets
the decimal value from data row.

        /// </summary>

        /// <param
name="fieldName">Name of the field.</param>

        /// <param
name="dr">The dr.</param>

        /// <returns></returns>

        public static decimal GetDecimalValueFromDataRow(string fieldName, DataRow dr)

        {

            return (dr[fieldName]
== DBNull.Value ? 0 : Convert.ToDecimal(dr[fieldName].ToString()));

        }

Tip of the Day: CodeSmith Template -- Load all foreign keys into a Dictionary object

Fri, 28 Aug 2009 21:48:39 GMT

I am a huge fan of CodeSmith. If you are not familiar with it, and you do any amount of coding at all, you owe it to yourself to check it out.

Below is some template code which loads the foreign keys of a table into a Dictionary object. It stores the name of the table and foreign key field name. As you can see, it generates a notice when it comes across a recursive relationship.

public Dictionary<string,string> GetForeignKeyTables()
{
Dictionary<string,string> dic = new Dictionary<string,string>( );

for (int idx = 0; idx < SourceTable.ForeignKeys.Count; idx ++)
{
string primaryTable = String.Empty;
string primaryKey = String.Empty;

  // To get the foreign key columns
  ColumnSchema col1 = SourceTable.ForeignKeys[idx].ForeignKeyMemberColumns[0];
        primaryKey = col1.Name.Trim();

  // To get the foreign key tables
        primaryTable = SourceTable.ForeignKeys[idx].PrimaryKeyTable.ToString().Replace("dbo.",String.Empty).Trim();
        if (!dic.ContainsKey(primaryKey))
            dic.Add(primaryKey, primaryTable);
        else
            MessageBox.Show("This table may contain recursive relationships. You must set those relationships up manually.");
    }

return dic;
}

Interview Question: Have you ever had an application launch fail?

Wed, 26 Aug 2009 23:01:11 GMT

I mainly ask this of QA people when I interview them, but I have started adding it to my general interview questions.

Let's face it, if you have been coding long enough, and release your application to the world, there's a 100% chance at some point something will go wrong. It's part of life and it's nothing to be ashamed of.. most of the time.

The key to answering this question is address it honestly, but with all "negative" questions, show what you have learned from it. For example, say you had an application launch, and when you turned it on, it didn't perform well because it was wildly successful. You could describe this, but make sure you say something like "now, before I launch, we create performance tests and build in performance indicators so we can detect these issues pre-launch, and monitor the application proactively." In a word --> what I learned from it.

One of my classic "flubs" was for an auction I wrote the software for. It was live on TV, and the client had me make a database change the night before going live, and we didn't get a chance to adequately test the change (which is to say, nothing more than my rudimentary testing, and my client just didn't have the time). As the auction commenced, the save method was failing on certain items, and I quickly saw the problem and fixed it LIVE on national TV. My lesson --> NEVER let a client tell me they don't have time to test, and no one even knew it was failing.

As an aside to this, the reason no one knew there was a problem is I had very good error handling/trapping and logging. The application adequately handled the issue, and I was able to monitor the application logs remotely, and immediately saw the problem and knew what the fix was.

How I have used reflection

Tue, 25 Aug 2009 05:12:16 GMT

Earlier today, I blogged an interview question about reflection. Earlier this year, as part of the interviewing process I was tasked to write a simple calculator. There would only be 2 integer inputs with a single operation. For example, if the invoked the program, and entered in 1 U 2 (U being the operation for addition), the program would output 3.

The assignment also mentioned they would want the possibility to expand the operations later. Instead of just commenting on it, I decided to implement that into the design.

I won't go into retrieving the data from command prompt, but I will provide the project at the end and you can see how that is accomplished. I made it robust by accounting for spaces, etc. As a programming concept, you should always program defensively and assume the work (and you'll be glad with the results).

First, I created a base class each operand would inherit from, so that each works similarly. The base class OperationBase looks like this:

using System.Diagnostics;

namespace CalcLibrary

{

    [OperatorIndex("")]

    public abstract class OperationBase

    {

        private int value1;

        private int value2;

        private string errorInformation
= String.Empty;

        public int Value1

        {

            get { return value1;
}

            set {
value1 = value; }

        }

        public int Value2

        {

            get { return value2;
}

            set {
value2 = value; }

        }

        public string ErrorInformation

        {

            get { return errorInformation;
}

            private set {
errorInformation = value; }

        }

        //NOTE: We may want
to return a string as the division will round every time, but we will keep this as
an int

        public abstract int Calculate();

        protected void ErrorHandler(Exception ex)

        {

            try

            {

                //While
in a production app we would want to hide the internals of an error, in this app we
will show them

                this.ErrorInformation
= "An unexpected error occurred (" + new StackTrace().GetFrame(2).GetMethod().Name
+ ")-" + ex.Message;

            }

            catch 
{}

        }

    }

}

You'll notice this abstract class defines taking two int
inputs (Value1 and Value2), handles the errors, and forces every implementation to
provide a definition of the "Calculate" method. When inheriting from this class, any
operand will be very simple to define -- all it needs to do is determine what to do
for a Calculation, as seen by the addition operand implementation.

namespace CalcLibrary

{

    [OperatorIndex("U")]

    public class AdditionOperand : OperationBase

    {

        public override int Calculate()

        {

            return this.Value1
+ this.Value2;

        }

    }

}

The next task was to determine which operand to use given
the user's input. We could write an "if" statement or a factory method, but I wanted
to make sure if anyone came in to add a new operand, they would not have to change
any code -- just add a new class, inherit from OperationBase and implement
the Calculate() method. To accomplish this task, I decided to use reflection.
By decorating each Operand class with an attribute, I could designate how it reacts
to the inputs. 

First, I needed to define my attribute:

using System;

namespace CalcLibrary

{

    [System.AttributeUsage(System.AttributeTargets.Class)]

    public class OperatorIndex :
System.Attribute

    {

        public string OperatorId
= String.Empty;

        public OperatorIndex(string operatorId)

        {

            OperatorId = operatorId;

        }

    }

}

Next, I need to decorate my operands with the appropriate
attribute. Again, I will use the AdditionOperand, which is indicated by the "U" notation.
When I define my class, I decorate it with the attribute letter I want to use to define
that function.

> 

    [OperatorIndex("U")]

    public class AdditionOperand : OperationBase

Now that I have
defined my operations, I need to use them. I created a publically exposed static class
called CalcEngine which loads all the operations, validates the inputs, and
processes the calculations. I created this as a class library so it could be used
with a console application (as it is being called from in the supplied example), a
web application, etc.

In the constructor,
I call a method LoadOperators() which uses LINQ to Reflection to quickly
retrieve all classes of type OperatorBase and have the OperatorIndex defined.
I load the resules into a dictionary object so I can quickly retrieve them for my
calculations. Below is how I load the operators using LINQ to Reflection.

private static void LoadOperators()

        {

            //Using
LINQ to Reflection, load all classes from the assembly that inherit from our base
Operator type, 

            //and
have the attribute set into a dictionary, so we can quickly reference the operator
we want

            operations =

                (from a in AppDomain.CurrentDomain.GetAssemblies()

                from t in a.GetTypes()

                where Attribute.IsDefined(t,typeof(OperatorIndex))

                where t.BaseType
== typeof(OperationBase)

                let attribute
= Attribute.GetCustomAttribute(t,typeof(OperatorIndex)) as OperatorIndex

                where attribute.OperatorId
!= ""

                select 

                    new OperatorDetails

{

    AssemName = a.GetName().Name,

    ClassName = t.FullName,

    OperatorId = attribute.OperatorId

}).ToDictionary(p => p.OperatorId,p => p);

        }

The main Calculate method
validates the input, retrieves the right operand key from the dictionary, late binds
to the proper OperatorBase class and invokes the Calculate() method,
as seen below.

                //locate
the correct operator from our dictionary

                OperatorDetails operatorInfo
= operations[mathOperator];

                //dynamically
load the operator class. I chose to do it using reflection so that we wouldn't need
a

                //factory,
which would need to be changed every time a new operator was added.

                //ENHANCEMENT:
you could actually detect other assemblies and load them as well

                Type calcClass
= Type.GetType(operatorInfo.ClassName);

                OperationBase calculator
= (OperationBase) Activator.CreateInstance(calcClass);

                calculator.Value1
= value1;

                calculator.Value2
= value2;

                int calculatedResult
= calculator.Calculate();

>>
>
 
Using
a console application, it looks like this:
 
Here's the sample code to look at and play with.. Enjoy!

SampleProj.zip
(89.4 KB)

Topical: The use of the var keyword revisited

Tue, 25 Aug 2009 04:28:04 GMT

Today has been an insanely busy day, but I have so much I want to blog about, and this one won't wait. A few days ago, as I was using some code I found on the net, I commented here about the over-use of the var keyword.

Seems I am not the only one who has an opinion on the matter. I subscribe to the CodeProject newsletter, and each issue features a survey. This week, the survey relates to the opinion of the var type in C#. You can see the survey results here. Make sure you click through to the "optional text answers" for some funny comments (and a few relevant ones as well).

The interesting thing to note from the survey is that the answers tend to skew towards the "never use that scenario" range. The two areas where it is most prevalent is with LINQ, and with anonymous types, which makes total sense.

Tip of the Day: Technical Interview question: What's Reflection?

Mon, 24 Aug 2009 14:27:02 GMT

Question: What's reflection, and how have you used it to solve a problem?

Answer: Reflection is a way to look at assembly metadata and look in and see what is contained. It also allows you to use late binding and call methods within those assembles.

For the second part, a simple explanation is all you need to show that you understand how it is used.

So what if you've enver used reflection? First, shame on you (kidding!). It DOES serve a very important purpose and allows for some great solutions, especially at an architectural level. If you've never used it, I recommend immediately trying it out, and you'll find many, many uses. Here's a tutorial I found that looks decent. That way, when asked this question (and I get this one a lot) you can answer how you *might* really use it. Honestly, you've probably used it and didn't realize it if you've added certain attributes to your code.

I have used reflection for everything from identifying certain classes and functions. For example, for a coding sample, I used LINQ for Reflection and attributes to identify classes which supported certain calculations. By doing this, I could add more functions dynamically and the UI would pick it without changing code. Since LINQ for Reflection is not discussed much, I'll post some about that later.

There are some costs associated with Reflection though. Speed! Late Binding is slower by it's nature, as well as all the processing looking for methods, so plan and use wisely!

Useful Links -- An overview

Sun, 23 Aug 2009 16:28:00 GMT

As a full time developer, I search the web... a lot. If you are writing a lot of new code without at least searching to see what exists, you're either getting paid by the hour (or line of code), stubborn or a glutton for punishment. Even if I don't use it, I can get some guidance on what someone else tried, and how it worked out before I start coding. Granted, it usually requires a lot of refactoring the code to my standards or needs, but it's a great start.

As I was thinking of things I wanted to put on my site, I realized it would be nice to share my "favorites"...sort of. If I found something useful, I wanted to be able to show what it was, how I found it useful and where someone else can find it. In a way, I am also helping to promote someone else's hard work and improving their search engine visibility to return the favor of their sharing their work.

Out of this, I came up with an idea for a "Useful Links" section. I wanted to be able to add links and commentary, and also add it to my Activity Aggregator to show help show the content of the site has changed. Later, as I was using Bing, I got the idea to add some webthumbs to enhance the page graphically, so the reader would know what the site looked like before going there. I also needed to add an admin page for creating the useful links (and ultimately maintaining them -- which is on my TODO list). I'll also leave out the icon creation part, although I really need to farm out for a new cool looking icon, which is also on my list of things to do.

I'll skip the admin section, as it's just data entry fields. The process for creating the entries does change a bit, as I needed to do a few extra steps.

Save the UsefulLink class
Default the webthumb image to a default "safety" image in case we can't get a webthumb
Make a request to get a webthumb image of the target site
Once the image is retrieved, update the UsefulLink record to point to the new webthumb
Update the Activity Aggregator to show we have a new useful link.

Step 3 is where things get tricky. How in all getout do we get webthumb images? There are controls out there you can get, and they are reasonably priced as well. But I decided to keep searching so I could write this one on my own, as it seems like an interesting challenge.

My next thought was to create my own service to do this. There's plenty of code out there, but the easiest way to do this would require some WinForms programming. Don't get me wrong, I LOVE programming WinForms. The problem is I don't want to have to install it everywhere I am at, as I need a service. I could possibly create a Web and Windows service to do this as well, but that seemed overly complex. So I did a search, and I found this, which is a service which does it for you. What's even nicer is that they expose a nice API to use. As of now, the first 100 images a month are free, and after that, the fees are very reasonable. Even though I doubt I will go over 100 images per month, I am so impressed I may pay just to keep the service going.

I was also able to find some c# code to make learning the API fast. I did end up changing it some, but in general it worked very well. You can find it here.

So when the service returns with my image (I used the medium size), I save it to a thumbs directory (had to add write permissions to the directory, or I got an obscure GDI+ error), and call a method on my UsefulLink class to update the record with the thumbnail image. I name the image with the current date and time so that the names will be unique as well.

Finally, once I have downloaded the image and updated the UsefulLink record, I add a call to my Activity class which creates an entry for the Activity Aggregator. As I add more items to throw into the Activity Aggregator, I am considering refactoring things to do some delegate multicasting for all the updates, or perhaps creating a factory where you provide class (should be easy since my business objects share the same base class) or interface, and it knows how to create the activity record instead of making individual calls. That's on my list down the road. :)

Here's what the Activity Aggrgator looks like, with a special Useful Link icon():

And here's what the Useful Link section (which has the webthumbs) looks like. I will only be showing 10 at a time to save web page real estate. But I also don't want to lose older links off the page. I am debating now whether to use paging, or just have a smaller hyperlink-only section below the most recent links. I am leaning towards paging, as I have a very neat service I want to implement which makes paging and sorting incredibly fast and easy (more on that someday.. I need to upgrade it to user .Net 3.5 functionality before I post it).

WebThumbs working.. but an aside about VS.Net 2008's var keyword

Sun, 23 Aug 2009 06:09:25 GMT

Today, I was super-dad AND got a lot of coding done, and I managed to get my useful links controls done for my site here. It was actually a complex process to get things like the webthumbs integrated, update the activity aggregator, create an admin page. The end result needs some cleanup, but I think for a first run, it came out nice. Tomorrow I will blog on the details and some code on how I did everything in case someone decides they want something similar.

Tonight, I am tired. But as I was coding, I came across some code for accessing my webthumbs, and something struck me. In .Net 3.5, there's a new keyword "var" which allows for anonymous casting (sort of). When it compiles, the underlying code is cast to the correct type, and in using the var typed variable, it acts like the cast-type. It would definitely speed up development if you used it a lot. For those old-school VB fans, it really reminds me of the variant data type (which it is not). Read more about it here if you want some details.

However, as with all things, there is a cost. For me, it's readability. In English anyways, we read left to right. When I see a "var" vast variable, I have to keep reading to understand the type, then see how it is used. Not too difficult (unless it is coming out of a function or LINQ query), but it does take a little more time to figure it out. For example..

var doc = new XDocument(

                new XElement(

That being said, you can get around using it by declaring the variable to the expected type when you code it. I have some samples I will post later when I was using LINQ I forced myself to do this so I would fully understand what was happening in my LINQ. Here's someone else who is taking a similar take on it.

Anyone have any thoughts on that?

Tip of the Day: Interview Questions- Access modifiers in C#

Fri, 21 Aug 2009 04:06:04 GMT

Here’s another question which is very basic, and is mandatory to be able to answer for C# developers:

Question: What are the various access modifiers in C#?

Answer: public, private, protected, internal, protected internal

Depending on how the person answers the question (e.g. if it’s obviously an easy question for them, I move on), I may follow up with “So what does the protected keyword mean?”

So here’s the answers to each… you absolutely need to know what each of these are!

Public – accessible to anything

Private – can only be access by code in the same class or struct

Internal – accessible only within the same assembly

Protected – accessible in the same class, or in a derived class

Go here for some more info if needed: http://msdn.microsoft.com/en-us/library/ms173121.aspx

Tip of the day: Interview Question: What are some of the ways of maintaining state in an asp.net application?

Wed, 19 Aug 2009 19:34:53 GMT

Question: What are the various ways of maintaining state in an ASP.Net application?

A lot of people answer this with the different time of Session providers, but it’s not the same things. The key of this question is two-fold, do you know the object, and do you know when/how to properly use them (which leads to follow-up questions to gauge whether the person memorized the answer, or truly understands the concept).

· Session

· ViewState

· Application

· Cache

· Cookies

· Hidden Fields

· Query Strings

· Profile Settings

The big ones I look for are Session, ViewState, Application and Cache. If they answer that, I drill down a bit for understanding. For example, I might ask:

Question: How does application and cache differ?

Answer: They are both globally available to an application, but with cache, the server can free this up if it needs resources. Additionally, you can expire it after a predefined time, or is a file changes, etc.

Question: What are the dangers/concerns of using viewstate?

Answer: Page size, performance, security, etc..

The bottom line is that this question is fundamental to ASP.Net development, and it’s important you fully understand the implications of each. Failure to answer this question and any follow-ups is definitely damaging when I perform interviews.

Tip of the Day: Technical Interview question: The difference between a abstract class and an interface

Tue, 18 Aug 2009 15:02:10 GMT

I've been doing technical interviews for about 5 years now for .Net, and hired a lot of developers in that time. As a result, I have become proficient at quickly assessing a level of technical expertise as well as how a developer may fit within an organization. I will blog another time about what characteristics I look for in a candidate, but for now, I will go through some of the technical questions I ask, answer them, and explain why I ask the question.

Question: What's the difference between an abstract class and an interface

Answer: They have some similarities in that they both define abstract members which have to be implemented. An interface is really just a contract where you are stating "if I implement this interface, I will implement these methods". However, an abstract class can have an implementation, where an interface cannot. An abstract class can also have constructors and field data.

One advantage of an interface is that you can implement more than one interface per class, but you can only inherit from one class.

Note there's a lot more you could talk about with them both (and you don't want to overtalk any question), but the above will demonstrate you have a good knowledge of OOP design, which is what I was looking for. It's surprising how many developers cannot get this question right.

To learn more, here's a good article which discusses them in more detail (more than you'd need to answer the question for sure, but good knowledge to have!)

Tip of the Day: Get the Application Architecture guidelines!

Mon, 17 Aug 2009 00:21:50 GMT

As developers, we tend to get stuck in development boxes. By that, a lot of times you're so busy heads down, things change around you and you don't get a chance to do different things unless a problem comes up and you research the solution to it.

As new developers, the amount of information available can seem overwhelming. When do I use a web service? What are Design Patterns? What's the recommended way to..... you get the idea.

Fortunately, there's a guide on CodePlex which present high level concepts and recommendations for architects and would-be architects. It's a great reference, and best of all, it's free! If you have not downloaded it, I highly recommend you rush here and get it.

Search results.. and humor

Sun, 16 Aug 2009 17:19:47 GMT

Decided to look at my web stats, and when I was looking at the search criteria people were using to find my site, I had to laugh at this one: hate llblgen

I wonder if someone else was at the point of frustration I was. All I can say is this -- don't blog about it!! :) I really ought to categorize this as a "Trick or Tip".

Tip of the Day: Creating an Extension method to convert RSS pubDate to DateTime

Sat, 15 Aug 2009 20:18:49 GMT

I needed to use LINQ to XML to grab some RSS feed information into a BusinessObject I created to save to a database. Here's what I needed:

var activityList = from e in doc.Descendants("item")

                   select new RubiconPortal.BusinessObjects.Activity

{

   ActivityTypeID = ActivityTypes.Blog.Code,

   ActivityDate = e.Element("pubDate").Value.RSSDateTime().ToShortDateString()
+ " " + e.Element("pubDate").Value.RSSDateTime().ToShortDateString(),

   ActivitySummary = HttpUtility.HtmlDecode(e.Element("title").Value),

   ActivityDetailsURL = e.Element("link").Value

};

Since the pubDate comes across in a format which is different
than I wanted, I decided to write an extension method called RSSDateTime() to convert
to a DateTime, from which I can format any way I want or work with. Here's the method:

public static DateTime RSSDateTime(this string date)

        {

            DateTime d;

            if (DateTime.TryParse(date, out d))

            {

                return Convert.ToDateTime(date);

            }

            return DateTime.Now;

        }

Logging Blog Activity to my Activity Aggregator

Sat, 15 Aug 2009 20:13:22 GMT

I have to get some landscape rock put out before my home owner's association has a cow, but I decided to do some more work on my activity aggregator. Today, I decided to integrate my blog feed into it, so when I post here, it will automatically update this activity on my home page (and soon to be in my developer's area).

Here's what the end result looks (for now).

Doing it was fairly easy with the design I implemented in my last post. My BlogFeed class inherits the BaseFeed class, which means I need to implement the ParseFeed() method. Since the RSS feed from my blog is XML, I was easily able to adapt the same code from my TwitterFeed class to work for this RSS feed (which should actually work for any RSS feed I pass in).

I also created another Extension method (for practice) to convert the RSS feed date time to a C# DateTime object. I will post that code as "Tip of the Day" but I have to give Dan Wahlin credit for it, as I adapted some sample code he provided.

Here's how the RSS feed (aka BlogFeed) uses LINQ to XML for creating my activity object.

    internal class BlogFeed : BaseFeed

    {

        public override int ParseFeed(XDocument doc)

        {

            try

            {

                ReturnCode code
= ReturnCode.Success;

                if (doc
!= null)

                {

                    var activityList
= from e in doc.Descendants("item")

                   select new RubiconPortal.BusinessObjects.Activity

{

   ActivityTypeID = ActivityTypes.Blog.Code,

   ActivityDate = e.Element("pubDate").Value.RSSDateTime().ToShortDateString()
+ " " + e.Element("pubDate").Value.RSSDateTime().ToShortDateString(),

   ActivitySummary = HttpUtility.HtmlDecode(e.Element("title").Value),

   ActivityDetailsURL = e.Element("link").Value

};

                    foreach (Activity item in activityList)

{

    //We need to check and see if the item
exists

    if (!Activity.CheckEntryExists(item.ActivityTypeID,
item.ActivityDetailsURL))

    {

        int results
= item.Save();

        if (results
!= ReturnCode.Success.Code)

            code = ReturnCode.Failure;

    }

    else

        return code.Code;   //we
can break once we hit one we've already logged (for performance reasons

}

                }

                return code.Code;

            }

            catch (Exception ex)

            {

                ErrorHandler(ex, "An
unexpected error occurred in TwitterFeed.ParseFeed() - " + ex.Message);

                return ReturnCode.Failure.Code;

            }

        }

    }

My next step will be to integrate some AJAX so when
the user hovers over the link, they can see things like the date, more of the topic,
etc. I also need to integrate my "Useful Links" dicussion as well.>

Creating my activity aggregator

Fri, 14 Aug 2009 06:40:31 GMT

Tonight was a very enjoyable night of coding. I created the first phase of my "activity aggregator". I actually had a more clever name for it, but being tired, it slips my mind right now.

Currently, I post several places.. short updates for on Twitter. Longer discussions end up on here, my blog. I have some other sources I plan on integrating over time, such as links I found useful (similar to Digg, but also where I can place why I found it useful). That means growth, and when it comes to design, it's best to design change into it up front.

The first thing I needed to do was create my table and business object to collect these activities. In my table, I store ActivityDate, what type of activity it was (foreign key to another table -- ActivityType), a brief summary of the activity text, and finally the url someone interested could click on to get more information. The internal members of my activity class look like this:

   15    
    #region Private Members

   16 

   17         private int activityID;

   18         private int activityTypeID;

   19         private string activityDate;

   20         private string activitySummary;

   21         private string activityDetailsURL;

   22 

   23    
    #endregion

Each private member has
a publically exposed property.

Most of my activities will
have XML feeds, such as the RSS feed of my blog, and the Twitter API. Therefore, I
enforce a similar implementation by creating an abstract base class, called BaseFeed,
which looks like this:

    1 using System.Xml.Linq;

    2 using RubiconPortal.Common;

    3 

    4 namespace RubiconPortal.BusinessObjects

    5 {

    6     internal abstract class BaseFeed :
BaseClass

    7    
{

    8 

    9    
    public abstract int ParseFeed(XDocument
doc);

   10 

   11     }

   12 }

So now I have a "contract"
that I need to use to have a similar method for any activity I want to log. I could
have used an interface for this, since there's no true implentation here, and I may
refactor it later to do so, but I do have some ideas where I may want to provide some
implementation, so that's why I chose an abstract class.

So the first item I wanted
to do was implement capturing my Twitter
posts in this activity, since I currently don't have a way to capture and post
them on my site. I will add the rest of the activities later. In a previous post,
I described how I took the Yedda Twitter API and modified it to return XDocuments,
and here's another chance to take advantage of that change with LINQ.

When I post to my Twitter
feed, I want to make sure my home page automatically reflects this activity. So I
implement a TwitterFeed object, which implements the BaseFeed method ParseFeed. Using
LINQ to XML, I pull out the pieces of the response I want, and populate the public
properties of my Activities class, then save my activity. Here's what my TwitterFeed
class looks like:

    1 using System;

    2 using System.Linq;

    3 using System.Web;

    4 using System.Xml.Linq;

    5 using Rubicon.Common;

    6 using RubiconPortal.Common;

    7 

    8 namespace RubiconPortal.BusinessObjects

    9 {

   10     internal class TwitterFeed :
BaseFeed

   11     {

   12         public override int ParseFeed(XDocument
doc)

   13        
{

   14        
    try

   15        
    {

   16        
        if (doc != null)

   17        
        {

   18        
            var activityList
= from e in doc.Descendants("status")

   19        
                   
           select new RubiconPortal.BusinessObjects.Activity

   20        
                   
           {

   21        
                   
               ActivityTypeID
= ActivityTypes.Twitter.Code,

   22        
                   
               ActivityDate
= (e.Element("created_at").Value.ParseDateTime()).ToShortDateString()
+ " " + (e.Element("created_at").Value.ParseDateTime()).ToShortTimeString(),

   23        
                   
               ActivitySummary
= HttpUtility.HtmlDecode(e.Element("text").Value),

   24        
                   
               ActivityDetailsURL
= "http://twitter.com/" + e.Element("user").Element("screen_name").Value

   25        
                   
           };

   26 

   27        
            foreach (RubiconPortal.BusinessObjects.Activity
item in activityList)

   28        
            {

   29        
                item.Save();

   30        
            }

   31        
        }

   32 

   33        
        return ReturnCode.Success.Code;

   34        
    }

   35        
    catch (Exception ex)

   36        
    {

   37        
        ErrorHandler(ex, "An
unexpected error occurred in TwitterFeed.ParseFeed() - " + ex.Message);

   38        
        return ReturnCode.Failure.Code;

   39        
    } 

   40        
}

   41 

   42     }

   43 

   44 }

Within the ParseFeed
method I am using LINQ to XML to populate my business object calling the save()
method to write it to the database. As you can see, using LINQ to XML can be
a lot simpler than using XML/XPath. Once in the database, I can query it in my user
control, and display it on my home page here.

Now, when I make my Twitter
post, all I need to do is take the XDocument the Twitter API returns, and pass it
into the ParseFeed method, which looks like this...

   35        
            //Post
my tweet to Twitter

   36        
            TwitterAPI twit = new TwitterAPI();

   37        
            XDocument doc = twit.UpdateAsXML(Settings.TwitterUserName(),
Settings.TwitterPassword(), txtPost.Text);

   38 

   39        
            //Save
it to the activity table for displaying the activity

   40        
            TwitterFeed feed = new TwitterFeed();

   41        
            feed.ParseFeed(doc);

Simple and neat! Now when
I implement it for my blog, it will be just as quick and easy!

Props go out to this post I
snagged an extension method for formatting the Twitter posting date to something a
human can use (and my C# class can use to manipulate and save!)

Some neat things I found today...

Wed, 12 Aug 2009 05:31:11 GMT

Tonight was a short night of development, as my folks were in town as my dad needed to go to the doctor. I did get some database work done, and my business objects done. I use a hybrid of Rockford Lhotka's CSLA. I don't need all the functionality (such as layers of undo) so I trimmed them back the amount of functionality I needed and created CodeSmith templates to generate my classes. Let me just say I can code really fast now. :) If you haven't taken a look at Lhotka's Business Objects book, I highly recommend taking a look at them. I began using his concepts in VB, and they have proven very reliable and scalable.

QDJ: Do you use ORM's, and if so, what flavor do you like?

I have to admit, I am not the biggest fan of the various ORMs I have tried. They do serve a purpose though, but I have found most inflexible. I am currently using nHibernate, and while they make themselves readily available to code generation, so far, it seems like a lot of code. See my previous comments about another ORM I tried. My brother uses it, and seems to be happy with it. I just thought the learning curve was very steep, and the documentation was very lacking. I took a beating for that opinion. :)

So tonight, I want to post a couple of links I used today. Soon there will be a control for this on the Rubicon Computing site, but until then, I will post them here.

First, I referred to this before, but here's a site with a lot of good links to various "cheat sheets". Some are really good and useful. You can find those here.

Next, I found some neat add-ins for Visual Studio 2008. The first is the Source Code Power Toy. It outlines your code in a treeview, which makes navigating your code, especially in complex classes, very easy. Best of all, it's free! It's available for VS2005 as well.

I also installed the Power Commands for the VS 2008 IDE. It has some useful right-click functionality, such as opening a command prompt, and opening the containing folder, and that's just a small glimpse of what it can do. It seems to be well documented, and I look forward to exploring all it's functionality. And best thing, this one is free too.

I'll probably post some useful CodeSmith templates I created. I love CodeSmith, but sometimes it's tough to find out exactly how to do things, so I will spare the world the trial-and-error where I can. In the current project I am working on, our team saved 1,100+ hours, and over $50,000 dollars last month alone by generating nHibernate code from the templates we created. Yeah, I earned my rate last month for sure. :)

As we march across the Rubicon, we have Admin pages!

Tue, 11 Aug 2009 05:05:59 GMT

Tonight I didn't get as much time to work on the site as I would have liked, so I focused on getting the admin pages up on the production server so I could do some "behind-the-scenes" work remotely. This required some security, which I started last night, but the data migration for that was a bit more daunting, so I needed to finish it tonight. While the authentication providers and controls do handle a LOT, it has an interesting learning-curve, and deployment can be a challenge as well. All-in-all, it sure beats writing all that code by myself.

I tried to use a lot of caching and cached settings to help improve the performance on certain pages, especially my client list. On my admin pages, I made sure to create a means to reset that cache without having to do a complete server reset. Actually, the same approach I took would work well for high availability sites, as the method I used to complete this would not require a server reset to re-load systems. When I was int he banking industry, high-availability was a huge issue, and simple config changes meant waiting for a scheduled system outage or worse, an emergency outage. When I redesigned that site, that was one of the top priorities I had.

It occurred to me how much time it takes to set up the infrastructure of a site: master pages, common libraries, configuration files, CSS, etc. Once those are done, if done properly, the rest of the site should go fast. One thing I have found to speed that up was the use of Visual Studio Project Templates. Combined with code generation like CodeSmith, you can really generate web sites extremely fast, and get on to coding the "fun" items. I will write about both of those in the future (CodeSmith and Project Templates) once the site is stabilized.

Tomorrow night may not have a lot of development, as my parents will be in town. Later this week, I will be coding my next control: the activity feed. When posts and feeds are made or read, this control will snag it, and place a brief "teaser" on the home page.

More progress on my site -- Client List!

Mon, 10 Aug 2009 04:58:40 GMT

I finally managed to get my client list online today. From a technological standpoint, it was pretty straight forward. I store the information in the database, and use my CodeSmith templates to create a class for extracting the data, and then use a Repeater to present the information in a table format. I still need to make some changes to it, but all in all, it works well. Since the data won't be changing often, I did cache the data to make it come back faster.

I started working on security for my Administration pages. I need to get that set up before I can activate the admin pages, but I have run into some issues getting it all configured. I ran into this once before with the ASP.Net forms authentication security provider, but this time is a little different, as I only want to secure one folder. Certainly not too difficult to do, but not as easy as I would have hoped either.

Once I get the security and login page worked out, I'll begin working on my "links" page. The idea here is that when I blog, or post to twitter, or a few other ideas I have, it will update the dark blue control on the home page with a summary and hopefully someone will click through to get the rest of the details. This should be fairly straightforward to do. Since most of the services respond in XML, I'll just use a factory method to instantiate the proper object, which will know exactly what information I want to extract from the XML feed. As I add more items I want to track, I will simply have to implement the same interface and it will plug right in to my "updater". For the items which return XML (e.g. RSS or Twitter), I will use LINQ for XML to grab just want I want and populate the data right into my classes.

Which brings up a point...

I could probably do this almost as easy with XPath. When does it make sense to move to the more "sexier" technology as opposed something proven and works well? For example, a lot of times, when a new technology is rolled out, it tends to be buggy and some of them historically have not performed well (e.g. early XML for those who have been around a while). All things equal, when does it make sense? Just a rhetorical question, but one I got hit with recently.

I was in a technical interview for a job I wasn't planning on taking (drive was too far -- the company I was representing knew this as well, they just wanted me to be on their radar for the future). I was asked about a particular implementation of the new List object. Honestly, I know how to use the List object, and he was asking about some of the internals I really hadn't needed to know.

If I was having performance issues, I would want to know, and then I would look into it further. In this case, I was able to provide at least 4 other reasonable implementations based on the criteria I was given, yet, I still couldn't get the "sexy" answer he was looking for. At what point does it really matter? For my part, I didn't like NOT knowing, and I did look it up when I left, but in the big picture, when does it become relevant? In my book, the practical solution to a relevant problem always supercedes technical "sexiness".

A not-so-shameless plug

Fri, 07 Aug 2009 05:02:11 GMT

I finally got around to updating my resume, and I pasted it temporarily on my home page at Rubicon Computing Solutions. That's my company, and it's been a great run of 13 years. I say temporarily simply because it will better positioned later, but I realized I really should have it on there so it gets picked up by some search engines, recruiters and in general people looking for .Net development in the Phoenix area.

I am in some talks with some other very senior developers I have had the pleasure of working with over the past couple of years about banding our talent together. I've tried that before, but these developers have been on their own for a long time, so we have a very similar background and strong work ethic to build upon. I have always struggled in the past with partnering up with other developers, as I have very high expectations of any project I work on. In fact, this is why I have had trouble hiring help, as my standards of quality aren't met by most developers without substantial coaching. These developers already have that skill, along with maturity and experience, which makes this a very exciting opportunity. Interesting how this economy drags some people down, yet others, like myself see it as an opportunity.

One of the limiting factors I have always had was that I was limited on the size of projects I could take alone. This changes that dynamic dramatically.

So if you're looking for some quality application development (web or windows), I specialize in quality service and coding in a Microsoft environment. I can work alone, with a team, or build and lead teams. You can find more details about those skills here. Thanks!

Yedda library, Twitter Responses and LINQ to XML

Wed, 05 Aug 2009 05:34:05 GMT

Tonight's coding session went by WAY too fast. I integrated Yedda's Twitter API into my admin pages so I could post directly without having to use another client or browse to Twitter to do it. The next step will be to read my blog feed and Tweet automatically about the topic. That's for another night though, as tomorrow night is poker night, and yes, I still play. :)

One change I made to the Yedda library (ok, two.. I ran into an issue with an error code 471 being returned, but a quick Google search fixed that (sometimes I how effeciently we coded before Google). I wanted to use LINQ to XML to parse out my response code. So Instead of returning the XML Document, I convert it to an XDocument using the Parse method, and return that, like this:

         public XDocument UpdateAsXML(string userName, string password, string text)

        {

            string output
= Update(userName, password, text, OutputFormatType.XML);

            if (!string.IsNullOrEmpty(output))

            {

                XDocument xmlDocument
= new XDocument();

                xmlDocument
= XDocument.Parse(output);

                return xmlDocument;

            }

            return null;

        }

Next, if I want to grab the status from of the post to Twitter, I can use LINQ as follows (in this case, I want the id so I can see if it was successful):

TwitterAPI twit = new TwitterAPI();

                    XDocument doc
= twit.UpdateAsXML(Settings.TwitterUserName(), Settings.TwitterPassword(),
txtPost.Text);

                    var status
= from s in doc.Descendants("status")

             select (string)s.Element("id");

                    bool found
= false;

                    foreach (string id in status)

    found = true;

I am sure there is a better way to determine if it was successful, but this will work for now, as there are other things I want to do with the response as well. Since this worked so well, I plan on converting all the XML calls to XDocuments so I can use LINQ to work with the response.

That's it for today!

Conditional Compilation and the VS2008 IDE

Tue, 04 Aug 2009 05:15:10 GMT

Today has been a very productive day in general for my .Net development. I came up with a few ideas of integrating Twitter with the site, as well as some longer range plans for using trending APIs for a concept I will tentatively call sociolytics^® (I would have preferred socialytics^®, but the name was taken, so I will coin both and trademark them both). :)

So today's topic will encompass some of the design considerations. First, I needed to create an admin page to allow me "behind the scenes" access to posting and functionality. I made sure to create the page it its own subdirectory to simplify access control to those pages. I created a separate master page for this section, as I might need more real estate for the controls which will reside on this page. Which brings up another topicI will bring up at some point --> control oriented encapsulation.

One of the controls was to allow me to post to Twitter directly from the page. I debated a couple ways to do this.. limit my control to 140 characters, or allow more, and do multiple posts. I opted one post per submit, as I want to make sure my posts are complete. I wil add a link to create "tiny URLs" via a web service next, to aid in quickly creating short links for things I want to tweet. I picked up a nice article on that over at CodeProject.

But the topic of this post relates to a cool feature in the Visual Studio 2008 IDE. Maybe this has been there all along, and I didn't notice it, but today I did. I needed to create a control which allows me to quickly encrypt values. For example, until I get OAuth implemented, I want to hide my Twitter credentials. However, when I post this functionality, I really don't want the world playing with this functionality if they manage to hit this page.

So enter the conditional compilation. I wrap the calls in the following code, and when I compile for release, it's not included. What's nice is that the IDE even reflects the code won't be available when compiling in Release mode. Pretty nifty!!

            try

            {

#if DEBUG

    if (txtValue.Text.Trim().Length > 0)

    {

        lblResult.Text = Settings.EncryptString(txtValue.Text);

    }

    else

        lblResult.Text = String.Empty;

#endif

            }

            catch (Exception ex)

BTW, thanks to CopySourceAsHTML for
making posting snippets so easy!

First Control -- RSS Feed

Sun, 02 Aug 2009 14:54:16 GMT

As the main site is developed, I'll detail what decisions I used to create the site, then a high level overview of how I designed it. Just a warning though, some of the decisions will seem very arbitrary, as they were. I made them simply because working on your own site gives you a luxury of trying things you normally can't do with a client. In my case, a lot of my decisions will be over-engineered, because I may want to re-use them later.

Of course, the first thing I had to come up with was an overall site layout. I won't go into that here, as one thing I will never profess to be is a layout guru. I got a decent design, and I set them up as a master page so the rest of the site development will go easy. I used VS2008 and C#, and began implementing AJAX where it made sense. For example, there's a control which updates the current time every 30 seconds or so, so I could use the update panel and timer control.

The first real functionality I wanted to add was a link to this blog. So I created a user control, and placed it on the front page. However, I do plan on posting a lot more here, so I knew it wouldn't be feasible to show every post, so I decided to limit it to the latest three posts. I wanted to display the title, the date and the first bit of the post to hopefully catch a reader's attention.

But reading from a feed from sites at two different hosting providers can be tricky. Not from a security standpoint, as RSS feeds are open, but more from a performance standpoint. Anyone coming to my portal site should be able to see the latest posts, and quickly. The fastest way of doing this would be to create a Windows service which periodically reads the feed, and stores the information in a database. However, I am not sure I would be able to install a Windows service on my service provider's server. So......

What I can do however is read the feed, and place it in cache. Periodically, I can expire the cache and re-load it, and unless you are the unlucky soul to have to wait while it loads, the majority of the users will have a quick response. For that poor soul who waits while cache is refreshed, I used Ajax and the UpdateProgress control to provide some visual feedback that the page is doing something.

The rest was pretty straightforward. I either request the XML from the RSS feed (or cache), and use XSLT to display it. It's been a while since I have used XSLT, but there is a lot of potential there, I expect I will be using a lot more of it in future controls. I created the class generically so that I could pull any RSS feed I wanted from it as well.

One great use I found for XSLT was on a high-availability web site which sent a lot of emails. We wanted to be able to change the email format frequently without bringing the site down. Using XSLT, we could change the email template files any time to create very nice HTML based email messages. I read a great article recently about calling C# functions in your XSLT templates using extension methods, which I plan to use extensively, as C# is my main domain. Maybe I will use them... I say that as I really would like to improve my XSLT skills, as I think the technology is highy underused in the .Net world.

So now I am playing with Twitter feeds and getting the rest of the site content set up. I also used the AJAX popup control to help prevent any 404 errors as I complete the functionality. If you've been putting off using the AJAX Control Toolkit for some reason.. STOP! The amount of functionality these controls offer is amazing, and you can't beat the price.

That's it for now! If you want more details on how I accomplished this or some sample code, just send me a comment. Upcoming posts will address the development of the rest of the site, along with some major wins recently using CodeSmith.

New web site, new technologies, and new horizons!

Sun, 02 Aug 2009 00:30:11 GMT

The past three years have been spent more managing teams of developers than actually doing development. On my current gig, I have gotten more of an opportunity to get back into the code, and I have to say, I mhave missed it immensely.

As a result, I have started doing coding purely for myself, and I have to say it has been immeasuably enjoyable. So I put my company's website back online, but this time it uses AJAX, RSS feeds, and soon, Twitter!

It's been an interesting and fun hiatus from pure coding, but now I am really looking forward to updating my skills again, and writing about it along the way.

This post will be the first "real" test of my onsite RSS reader. So in a bit, it should appear on the front page of my all new company portal site... Rubicon Computing Solutions!

New feature in .Net 2.0 Exception object

Tue, 13 Jun 2006 15:42:38 GMT

There's a pretty useful feature (IMHO) in the .Net 2.0 Exception object which I hadn't noticed before. The Exception object contains a new Data interface, which is essentially an IDictionary for applying additional values to the exception object. I am currently using it with my integration of the new VS2005 Enterprise Library into our framework.

I want to log exceptions to a database, but I have found it useful in the past to have an Error #. In the old days (VB 6, for example) I could usually look at the error number of an application and tell exactly what the problem was. When .Net came into being, we lost the error number, and there was no easy way to get around it. You could roll your own exception classes of course and add these properties, but this is only a limited solution because other exception handlers wouldn't be capable of handling the additional features by default.

Now this feature is going to allow me to take advantage of error numbers by classifying each exception type, and appending an error number to the exception object. I can use this information in my database to classify and group errors by type to identify weak areas in an application as well. Not Earth shattering, but still a useful feature full of all kinds of possibilities.

Tip of the Day -- Determine current database name using T-SQL

Tue, 16 May 2006 15:38:30 GMT

Still working on getting posts over at developernation.net, and ran out of time on a series I am writing. This week looks to slow down a bit, so hopefully by the end of the week I can finish my series on a web service for paging and sorting data. Until then, I just ran across a situation where I needed to programmatically determine the current database name from T-SQL. Sounds easy, right? Well, fortunately it is, but the function to do it is documented poorly, so I figured I would post a tip so others could find it easily.

SELECT db_name()

The documentation says you need to pass in the db id, as does the example. However, if you read very closely, it appears you don't need to pass in the id, and it will return the current db for the connection. I wish they would have followed the documentation standard of using optional parameters with brackets [], and it would have saved some time.

A change of directions...

Fri, 28 Apr 2006 15:38:06 GMT

So it has been hit or miss posting here, but I am trying to correct it by bringing on some additional help. I set up a new blog, developernation.net, and begun getting some content on there. Likely I'll crosspost on here too (my content anyways) but likely most new entries are going to be there first. I figured if I could get someone else on there helping doing some content, it will have more regular posts. This blog will continue, just a lag a few days on the content of theother site, and contain more personal observations.

So swing on by and pop in. I've started off with a bang, and I am in the process of posting a web service design I created and tested which handles paging and sorting of data on the server, which my initial tests have shown to be highly efficient. I am walking through the entire design, and by the end of the weekend I hope to have the series done and the code posted. If not, you can wait a few days and I will post it all here as well.

Thanks!

Something funny I remembered...

Mon, 27 Mar 2006 15:49:48 GMT

I was talking with someone this morning about bugs, and I remembered a request I received many years ago. There was a really large Access database project, and I had inherited it. Unfortunately, it had become a total kludge, and I continually requested the client invest the time and money in upgrading it into a more appropriate technology, such as VB.

As is often the case, when it comes to the money discussion, it's tough sometimes to convince a client a re-write is actually less expensive over time, especially when the scope has changed so many times, and looking forward it looks like it is going to do the same. This is actually where agile development methodologies are at their best. So in this case, when I explained that the changes would have a huge impact on the project, and it would likely introduce bugs into the system (they also didn't like to pay for testing, feeling they could test it in use), they advised me to continue.

Just as I predicted, the changes did introduce a lot of issues into their work processes. As I recalled the notes and admonitions I made regarding the changes, I received a rather novel and (to me) humerous response....

Here's the gist of the conversation...

(Client) This is an Access database, right?

(Me) Yes, it is.

(Client) And you are always running custom queries for us, right?

(Me) Yes, I do.

(Client) So maybe you could just run a query to identify all the bugs in the system?

(Me) If I could do that, I'd be retired and very well off right now..

Sometimes a poker face is a wonderful consulting tool. :)

Solution to the WinCV issue...

Wed, 22 Mar 2006 23:00:20 GMT

I had a great need again for WinCV today, and was beginning to work out in my mind how I would rewrite it, as I posted earlier. However, it hit me that Lutz Roeder's Reflector for .Net might actually do what I needed. It does, it turns out. I did have to modify the .cfg file to look at the new assemblies for VS2005, but once I did that, the search functionality worked wonders. So, even though it would have proven to be a great learning experience, I am going to forego putting a rehash together, and stick with something that works very nicely..

WinCV v2 revisited

Wed, 22 Mar 2006 15:44:55 GMT

I found some details on WinCV for VS2005 (or the lack thereof). As near as I can ascertain, if you have VS2005 only, and place WinCV on that system it will work for the .Net 2.0 libraries. I don't know how that works as it seems the information is hardcoded into WinCV.

So, it was such a great utility, and I think it lends itself to some great enhancements, so I think I am going to write a version which is VS2005+ compliant. Some features I want to add:

Quick linking to the help topic for a class/method
Ability to easily add external assemblies WITHOUT having to use the command line

I plan on keeping the same basic interface though, as it was simple and effective. Not sure how much I willl get to work on this, or how long it will take, but I will post it here and probably CodeProject when I get it finished.

WinCV, where for art thou?

Tue, 21 Mar 2006 13:48:01 GMT

Is it just my installation, or is WinCV missing from the latest version of .Net? Granted, I can still use the old WinCV by changing the config file, but why was such a useful tool pulled from VS2005?

If you've never used WinCV, check it out for VS2003 and prior version. It essentially lets you search the framework for a certain keyword. For example, if you want to find out which namespace "Registry" is in, type it in, and see the entire implementation. By using the configuration file, you can add additional assemblies for WinCV, to search your own libraries or those of third party vendors.

Rough night of poker..

Fri, 17 Mar 2006 05:39:58 GMT

I've been playing a bit of poker recently, and having mixed results. Earlier this year, I was on a tear, and couldn't lose. Lately though, it's been a bit dry. I played in a tournament on Sunday at a local casino, and finally made the final table again, and even did ok in te cash game leading up to it.

Tonight was a humorous night though. I decided to play again, as I am in the running for a finals tournament at the casino I placed on Sunday. First, I played against a handicapped player, and we came up with a device to help quadraplegics to play poker with less assistance than it normally takes. Now I just have to find the parts and see if I can put it together, as it looks like a very viable solution to help him. But secondly, I have to say tonights tournament was the "worst" I have ever had. Although I managed to stay alive for 2.5 hours (mainly due to the lack of playable hands or situations), I did not win a single hand. However, I DID manage to chop one, so I will count that as 1/2 of a hand, but all I won were half the blinds. If you count the cash game I played prior to the tournament, I think you could take that losing streak to 4 hours of not winning one hand. Fortunately, losses were minimal, as the hands I was starting with were poor quality, and I just rode out the blinds. I think that is the longest I have ever gone. What a test of patience!

Such is poker...

Web Service Issues Part II: The Underlying Connection was closed

Thu, 16 Mar 2006 05:19:42 GMT

Previously, I discussed how I worked around a firewall issue where the HTTPS port was re-mapped, and the return URL was different than the request URL as a result of that remapping. So I trudged on, and hit a real stumper. Here’s the new issue:

The underlying connection was closed: Could not establish secure channel for SSL/TLS. Inner Exception: The function completed successfully, but must be called again to complete the context

I ran across Jan Tielen’s blog post (http://weblogs.asp.net/jan/archive/2004/05/08/128394.aspx) where he provided a code snippet to override the GetWebRequest method in the Reference.cs file. I implemented it, and it worked great --- on my development machine! However, when rolled out to the same test environment, the problem remained. However, I modified it futher, and got it to work..

/// <summary>

/// Set web request properties here

/// </summary>

/// <param name="uri">uri </param>

/// <returns></returns>

protected override System.Net.WebRequest GetWebRequest(System.Uri uri)

{

System.Net.HttpWebRequest webRequest = (System.Net.HttpWebRequest)WebRequest.Create(uri);

webRequest.AllowWriteStreamBuffering = true;

webRequest.KeepAlive = false;

return webRequest;

}

Sort of. When I tried to use DIME with the above code, it gave me an error “Client found response content type of '', but expected 'text/xml'”. That was not going to work. I found some more code, and it seemed to work great once again, until I tried to make a DIME call. Here was that attempt.

protected override System.Net.WebRequest GetWebRequest(System.Uri uri)

{

WebRequest request = base.GetWebRequest(uri); ;

if (requestPropertyInfo==null)

requestPropertyInfo = request.GetType().GetProperty("Request");

HttpWebRequest webRequest = (HttpWebRequest)requestPropertyInfo.GetValue(request,null);

webRequest.KeepAlive = false;

webRequest.ProtocolVersion = System.Net.HttpVersion.Version10;

return request;

}

Once again, it worked fine during my WSE calls, but failed when trying to use DIME attachments with the following error: found response content 'application/dime', but expected 'text/xml'

To save any readers some time, I will go through everything I tried to resolve the problem, and finally, how I ended up resolving it. Here’s the items which didn’t work:

-- tried setting the SoapActor

-- tried turning off the Document protocol

-- tried setting the request and return URI

-- tried overding the GetWebRequest function a few different ways

-- tried using wsdl instead of asmx in setting up the Web Reference

-- tried setting the URI target/destination seperately

-- moved web service to the same machine as the calling web site (but still had to make an external call)

-- turned on tracing input and output and analyzed the logs created by WSE 2.0

So what finally worked? I ended up abandoning DIME, and encoded the file as a string, and passed it as an element of my XML. Here’s the code to encode the file as a string.

/// <summary>

/// Encodes the file in a Base64 string format.

/// </summary>

/// <param name="file">Name of the file.</param>

/// <returns></returns>

private string EncodeFile(HtmlInputFile file)

{

try

{

if (file.PostedFile.ContentLength > 0)

{

byte[] fsBytes = new byte[file.PostedFile.ContentLength];

System.IO.Stream fileStream = file.PostedFile.InputStream;

fileStream.Read(fsBytes, 0, file.PostedFile.ContentLength);

return Convert.ToBase64String(fsBytes);

}

else

return String.Empty;

}

catch (Exception ex)

{

//Handle the Error

return String.Empty;

}

What a trip it was to get there, but the resulting service has performed well, and I don’t have the issues I had with DIME. Don’t get me wrong, DIME worked great. But deployment of the web service in a secure environment proved to be quite a challenge. If you need more detail in resolving your issue, feel free to leave a comment or shoot me an email, and I will be glad to save you some of the pain I had to go through!

VS2005 Provider Model and the config file

Tue, 14 Mar 2006 17:52:31 GMT

Just a little tip, as I didn't read the error message generated as closely as I should have. I was working this weekend on the Microsoft Code Template for Building a Provider Based Feature and was migrating some existing libraries I had for VS2003 to take advantage of the features in VS2005.

First, let me say I love things in VS2005 like Generics, and the implementation of the Provider Model. I was migrating my data access libraries and error handling libraries, and was setting up some tests in nUnit as part of ongoing testing. Although I haven't changed my data and error handling models in a long time, I figured it was a great design idea to be able to change them dynamically using the Provider Model.

To make a long story short, I was running my tests for the data library, and when I invoked my Data Access classes, I was getting a "TypeInitializationException" error. I checked and double-checked my configuration file, and it appeared to all be correct. I looked at the InnerException, and it didn't seem to be much more help. However, I went further to look at the InnerException of the InnerException, and there's where I found the solution. The Rosetta Stone?

Only one <configSections> element allowed per config file and if present must be the first child of the root <configuration> element.

A quick check indicated that I hadn't made the configSection the first element. Doh!

So there are a few lessons to learn here. 1) Make sure your configSections is first (normally not a problem, just a cut and paste issue here) and 2) Make sure you dig REAL deep into the InnerExceptions for the details and 3) the new Visualizers in vs2005 were too cool and very helpful.

Hats off to the VS2005 IDE team! It's spawned a few visualizers I can think of, so if time permits in the future, I will be publishing those right here!

Web Service Adventures - The <To> header must match the value of an incoming message's HTTP Request Url if the soap receiver does not have an actor name.

Thu, 09 Mar 2006 16:12:20 GMT

At my current client, security is taken to a whole new level, which is a good thing. But as a result, sometimes there is more of a challenge to resolve issues you may not normally encounter. For example, I was tasked with writing a web service which would facilitate file transfers of documents and images from a web page (and Windows client), store them on a secured server, and serve them up to an authenticated user on the internet. To do so, we have to deal with proxy server issues and firewall issues.

After writing and testing the web service locally, I deployed it to our production server. Locally, it all worked fine. However, when I deployed the web portion of the application to our test server outside our intranet, the real fun began. The next several posts I will discuss the problems I encountered, and how I ultimately resolved the issue. Hopefully this will help any readers out there who have a similar issue, as well as become documentation for the process I used so I can later reference it.

The first issue I saw was the following error:

The <To> header must match the value of an incoming message's HTTP Request Url if the soap receiver does not have an actor name.

I'd love to give the person I found the solution at credit, but it's been such a long time I can't find the original document I used. I modified the solution to make it a little more "generic" so that the web service can be moved without requiring a recompile of the application.

First, you'll need to locate the Reference.cs file for the web service reference(for C# users. Reference.vb is the similar file for VB.Net, but all code here will be in C#). In this file, add the following reference:

using Microsoft.Web.Services2.Addressing;

Next, locate the consructor for the WSE portion of the Reference.cs. In this case, mine will be FileServiceWse(). Here's the code you'll need to replace the this.Url reference already in there.

public FileServiceWse() 

        {

            //these
two setting are the <TO> and Response URLs. For example, in our case the response
was

            //coming
back with the redirected port appended to the url.

            //The
Web service <TO> looked like https://mycompany.com/FileService/FileService.asmx

            //but
the response was https://mycompany.com:1234/FileService/FileService.asmx

            //The
endpointreference call to the Destination tells the application to expect the return
url to look differently than the

            //<TO>
reference

            string urlSetting
= System.Configuration.ConfigurationSettings.AppSettings["FileService"];

            string urlReturnSetting
= System.Configuration.ConfigurationSettings.AppSettings["FileService.ReturnURL"];

            if ((urlSetting
!= null) && (urlReturnSetting != null)) 

            {

                Uri sourceUri
= new Uri(urlSetting);

                Uri returnUri
= new Uri(urlReturnSetting);

 

                this.Destination
= new EndpointReference(sourceUri, returnUri);

            }

            else 

            {

                if ((urlSetting
!= null)) 

                {

                    this.Url
= string.Concat(urlSetting, "");

                }

                else 

                {

                    //this
is the default URL of the file service if all else fails.

                    this.Url
= "https://mycompany.com/FileService/FileService.asmx";

                }

            }

 

        }

What this code does is set the Destination property (if the FileService and FileService.ReturnURL settings are placed in the web.config file) to expect a different response than the requested web service URL. In our case, since our request was going through a firewall which remapped the ports, we had a port attached to the url for our web service which triggered this error.

The code also has failover. If I forget to make the settings, it will try the original URL reference. In my case the call won't work, but I believe in at least attempting to code some failover when human error can take place in moving files, etc.

But this only solved one of the many challenges I encountered in deploying this web service. Stay tuned for the next resolution to tricky WSE issues!

Not a record, but....

Thu, 09 Mar 2006 04:52:50 GMT

It's not a record for longest time between posts, but it sure has been a while. I finlly got off my butt and upgraded das Blog to the latest version, and enabled comments again. So now maybe it will be worthwhile to begin blogging again!

The past few months have been interesting to say the least. I have a catalog of things to post about, such as solving some bizarre web service issues with DIME (well, solution is not quite the word... a workaround is more like it) as well as beginning the trek into VS2005.

So if there's anyone still out there readin this, I do have a ton to write about, now lets see if I can find the time to do it!

It's the end of the world as we know it....

Fri, 09 Dec 2005 22:01:47 GMT

I just had to comment on this. First, the article: http://www.informationweek.com/story/showArticle.jhtml?articleID=174901240

A guy's XBox 360 fails, so he files a class action lawsuit. What the heck ever happened to RETURNING THE UNIT? I guess this loser (IMHO) can't be faulted. For years we've been blitzed by the legal community that someone has to be blamed. And in assigning that blame, there has to some monetary penalties for it. And when states get involved, it actually becomes a new form of “taxation“ in order to generate additional reveneues.

Want examples? Just look at all the antitrust legislation against MS. Just look at the lawsuits and huge penalties against tobacco companies. Cigarette packages have all kinds of warnings on them (and have for a LONG time) to the point they might as well have a skull and crossbones emblem on them, a la poison. Yet, states and individuals lined up to get cash from them. Take a look at http://www.overlawyered.com if you want plenty of things to get your blood pressure up.

But back to the original point. If the unit wasn't working, do what we did for years. TAKE IT BACK. If you don't think MS has a good unit, BUY THE COMPETITOR'S UNIT. Pretty simple. It worked for years. I wish he could be counter-sued if he loses. And I hope like hell he does. I have no great love of MS these days because I think they have turned on the development community to a degree, but still, fair is fair.

MSDN Universal Discount for MCSD/MCDBA

Fri, 07 Oct 2005 15:57:27 GMT

A year ago, I completed my MCSD for .Net. One of the attractive
benefits of this certification (as well as the MCDBA) was a $500
discount on a one-year MSDN Universal subscription during the first
year of certification.

Although the MCSD benefits page still lists this benefit
(http://www.microsoft.com/learning/mcp/mcsd/benefits.asp), they
quietly removed it as of April 2005. The text on the page still
states the following:
Rebates or discounts on a one-year subscription to MSDN during the
first year of certification.

If you call or write to get the certificate as I did, you'll get the
terse response it's no longer available, and they just haven't
updated the site. I figured I would help them get the word out since
they didn't deem it important enough to change on their site or
announce. It would be a shame if anyone expected this benefit based
on the MS web site information.

-------------------------------------------------------------------------

Above is what I posted to our local .Net community group on Yahoo. Now I am going to add some personal comments. Once again, MS has dropped the ball in supporting the developer community. Earlier this year, MS announced the MSDN Universal would not include the new .Net Team Development system (or some name like that -- I am too lazy to go look it up). Fortunately, enough of an uproar went out that they reversed that decision. Their waning support of VB also caused a petition/uproar. Likely, since the MCSD/MCDBA community is a lot smaller, there isn't likely to be a huge outcry on this issue.

This is a HUGE mistake on MS's behalf. Someone that is likely to spend the extra time and money to get certifications are the ones MS should really cater to. There's always been a criticism that the certifications are worthless, and that benefit alone made it real easy to justify spending the money on books, training materials and exam costs for achieving the certification. I won't argue the merits of the certifications here, but I have a lot of them -- MCP, MCDBA, MCSD for VB, MCSD for .Net (C#), and MCAD. Will I continue? I may have to given I am an Independent Contractor and it helps to get me in the door. Will I recommend it to someone not in my position? Not likely.

Don't get me wrong, the MSDN Universal is still a great deal. My disgust over this situation is that the benefit is still listed, as well as no announcement in April 2005 when they made this decision (or if they did, I sure didn't see it). I have been one of the most stalwart supporters of Microsoft over the years, and I have personally been involved in projects which have generated millions in licensing revenues for Microsoft in the last 10 years. The past 1.5 years I have watched MS anger the core base of developers.

I think this is indicative of the internal problems at MS, and why Google is going to be a viable competitor to MS. In a paraphrase of the words of Stephen King, and the Dark Tower series, MS has forgotten the face of their father. One of the reasons MS dominated the market over Apple was that MS supported developers way beyond the norm. In the name of profit, I think we are seeing this slowly change.

Bizarre error, bizarre solution...

Tue, 20 Sep 2005 22:50:34 GMT

Once again I have disappeared from blogging. Let's face it, I rarely get to do it. I also need to upgrade this DasBlog but I have been so busy I haven't been able to do that, even though someone kindly wrote me and told me it would solve my spam comment problem. Maybe this weekend...

But I wanted to blog because I found a weird problem, with a weirder solution. I wrote a Windows service in C# which periodically loads some data, based on the time since the last load. So dates are a bit important in this process.

First, the cryptic message: “Internal Query Processor Error: The query processor could not produce a query plan. Contact your primary support provider for more information”. A Google search turned up several solutions, but most of them relied on a service patch. What's wierder is that the error was intermittant. The procs would run fine in Query Analyzer, but not from C#.

Finally, I tried the unlikely. Instead of passing in my parameters as DateTime values, I passed them in as SqlDbType.Varchar, and in the proc made sure and converted them to DateTime values. Lo and behold, the problem went away.....Go figure!

Finally caught up to me...

Fri, 05 Aug 2005 13:33:34 GMT

I like poker. A lot. However, I don't like spam. A lot. Unfortunately the poker spammers have hijacked my blog comments. So until I upgrade my dasblog or come up with another solution, I am going to have to turn off comments. I am likely going to have time this weekend to resolve it, and possibly even start posting again as I think I have finished some of the side work I was working on. In the meantime, if anyone reading this want to post a comment, email me at daryl at rubiconcomputing.com and I will post it for you. Grrr.....

See the LLBLGen comments from July 18th...

Wed, 20 Jul 2005 20:31:12 GMT

OK, time for a little fairness in the world. When I wrote my blog entry on Monday, I was certainly frustrated with LLBLGen. Franz Bouma has responded to my comments about LLBLGen (little did I know I had such illustrious visitors!). So in fairness, I want to make sure anyone out there reading my blog sees those comments so they can see both sides of the review and form opinions on more than just my emotional outbursts, and my semi-apology for blogging while frustrated. :)

When code generation goes bad....

Tue, 19 Jul 2005 04:49:51 GMT

I have tons I need to blog about but no time to do it, as once again I am up to my head in projects. So this entry is going to be to vent....

One of my current clients is requiring me to use a product called LLBLGen Pro (see it at http://www.llblgen.com). I am certain it's a powerful product, and while it generates enough code to make a COBOL program to look efficient, it seems to perform OK, although my gut tells me this thing would be a pig in a high-demand environment. But here's my gripe -- the documentation is horrendous. I have spent at least 50 hours trying to get this thing to generate code effectively as well as consistantly. And even then, I don't understand a tenth of what's generated. I understand enough to make minor changes, and after a lot of wrestling, I can finally get it to generate code. OK, 50 hours may not seem like a lot to learn a new paradigm which might reap a lot of benefits later, but let me tell you what that 50 hours (billable to my client, I might add, since I begged them after 10 hours to scrap it) bought you. I managed to add 2 fields to a table, and add two tables. The two new table still don't work right.

Let's put that into perspective. First, I code lightning fast. Not spaghetti code mind you, but robust code which typically is right the first time. In that 50 hours, I could have re-written a good chunk of the app, and believe me, it needs it. Fortunately, I did my consultant's duty to bring that point up. It would have taken me three hours tops to make the changes which we are looking at 50 hours and still not working.

Second, the code is difficult to read at best. The project has fallen behind because of the insistance we use this tool, so they brought on two other developers. Guess what, they are having the same problems. They have spent two solid days now, and not one line of code written. Using standard objects, any developer with experience in .Net can peruse the object model quickly and begin coding. Not with this tool!

You can't compare CodeSmith, which I have praised before, with LLBLGen. LLBLGen is far more sophisticated, unfortunately to the point of being unusable. I know there are a few people who swear by it, and that's great, but I get paid to come in and make a difference fast, and LLBLGen has proven to be more an expensive hindrance than a solution.

OK, that's the end of the vent. I have been deploying some web services for another client, and once we have everything debugged, I have a ton of tips related to web services and deployment which I promise will save a ton of hours to other developers entering into this domain. Until then!

It just occurred to me...why extremes are bad in programming

Fri, 27 May 2005 17:28:46 GMT

Extremes in anything (IMHO) are typically not good. Extreme temperatures, religeons, attitudes -- you name it, likely there is a downside. In programming, it's no different. Now, while not a big fan of Extreme Programming, there's a couple of extremes from it that bother me. One is that you shouldn't include documentation. The other, which I suspect was someone's personal preference, was not to use the “Region” directives in C# (or I guess VB.Net either). Here's a little history...

This guy was a former Java programmer working for a large chip manufacturer. He was supposed to be a XP guru, so he was transferred to the local site to help a team in it's transition to the XP methodology.

Strike 1 -- he knew the methodology well, but he was by no means an expert in the language of the group. Why was this a strike? I guess technological bias in that his preferences to his other language directed him to want to make the .Net environment the same as a java environment.

Strike 2 -- It was his way or the highway. The environment was such that one or two developers had 95% of the say on development decisions. Part of the reason for this is that wacky trend in which everyone is ranked from best to worst in terms of raises, options and promotion (for more info what I am talking about, read this article, which is the same process -- Saying Goodbye). No one would ever argue with the two for fear of getting a bad ranking for being considered a troublemaker.

Regardless, I digress, but I do think it's important to understand why sometimes these extremes come about in an environment. I was a contractor brought on to bring some quick wins for a project, and it was my first (and likely last) venture into the XP methodology. They needed code, and they needed it fast.

One problem I addressed was the lack of uniformity on the project. We had three developers, which meant three different styles of programming. Even with XP, that meant one of us was alone, and the other two would spend the pair time arguning over which style was a standard and best (even though standards existed -- they were just never used because of informal rules imposed by the 2 'chiefs'). I decided to create a template which would standardize (and speed up) our development. I organized the code within the controls into regions, and deployed them onto our machines with anticipation I easily saved our team15-20 minutes each time we created a new control.

Alas, it was scrapped instantly. Why? Well, it seems in my templates, I placed the code into logical “regions” -- e.g. Public Properties, Public Methods, Private Methods, etc. I was “informed” (even though I had been using regions for a couple of months now) that regions were not allowed, because all they did was hide bad code. WHAT???!! Well, I liked the contract, and knew the results if I stood up to them, so I bit my tongue and moved on. It has bothered me ever since, but I never took the time to formulate an argument as to why regions are actually a good idea.

Why bring this up today after a year has passed? Well, I was coding something, and the constructor was hidden by a region. I was thinking “Hmm, if we just left the constructors out of regions, it would be easy to read, because the regions would hide the internal implementations I don't care about, yet at a glance I can see how to instantiate the object” (hmm, I think they call that encapsulation) and use it. Now that right there justifies the use of regions alone.... I can actually think of a lot of reasons to use regions, and I do it religeously where my client has no opition about it.

Just a flashback from the past.... anyone got a counter opinion? Regardless, it just goes to show extreme anything typically isn't a good thing in my mind. You have to be flexible in your approach to life if you plan on growing...

Self Promotion

Thu, 26 May 2005 23:33:35 GMT

Tentatively, my current project is set to end in October. No big deal there, as I have had absolutely no bench days in the past 10 years as an Independent Contractor. In fact, during most of those 10 years I have been working 55-80+ hours per week and having a great time doing it. I don't do the book thing or magazine article thing because quite frankly, I don't have time because I am busy doing billable work which pays a lot more. I havn't needed self-promotion thing either because almost all my business comes from referrals from current or past customers.

Then along come kids, and dang if you don't suddenly want to spend more time at home and improve their quality of life (and mine). My current project wants to bring me on full time, and we've had some preliminary discussions on it, and I am willing to take the pay cut in my pay for one simple thing: I want to work remotely and raise my kids in the country. Their attitude is like mine, which is that should be fine since I have a strong work ethic and can get things done, what does it matter where I work as long as I have a phone and internet connection. However, there are data security concerns and management concerns which would need to be overcome.

I have plenty of time, since barring disaster, the contract won't be over until October sometime. But I figure I will start self-promoting just in case someone from a company who doesn't mind remote employees stumbles on this blog. Towards October, I will go full bore trying to close something out, and in the meantime I plan on blogging much more so I can display what talents I can bring to the table.

If any companies out there that come up on this, and want a great employee (C#/VB developer with lots of SQL Server and architect/designer/coding and full-life cycle development) that brings a lot of experience, a great professional attitude and presence as well as the ability to code like the wind (and good code at that..), then drop me a line and let's talk.

Here's a resume just in case..

CodeSmith rocks!

Thu, 26 May 2005 23:19:32 GMT

I bought CodeSmith back in v2, but I was so busy I never got a chance to do more than play around with it. So now v3 is released, and I was looking at the improvements (like Intellisense) and decided I would take a look at it again. Boy, was I glad I did..

Don't get me wrong, I wasn't putting it off because I think code generation and templates are bad. In fact, quite the opposite. When I first started my business, I had a few people working with me part-time, and then finally full time as the business grew. What I found was that in the end, I apparently hold my coding standards to a higher value than others and I would end up coding 90% of the application myself. I realized quickly there were a few huge advantages to automated code generation. Here's a few:

Fewer errors (as long as you fix the templates as errors are encountered)
One developer can do the work of 4-5 once you get a good architecture set up
Standards enforcement is a no-brainer when you are all working off the same templates
You can spend more time on UI usability and data structure because 90% of the infrastructure stuff is done automatically
Changes are easy. Change the structure and regenerate the code, and you are off again.

I could go on and on about it. I had written a series of VB6 addins which I used based off Rocky Lhotka's BusinessObjects book for VB5. In hours I could generate almost all of my middle and data tier code. A tweak here and there, and I was doing the fun stuff like UI coding.

Along comes .Net, and my addins were irrelevant. I created a couple of quick and dirty addins, but I was so busy heads-down coding, I didn't have time to create new templates to reflect the impact of .Net. I did create some common libraries of functions which got me through a good chunk of redundant coding, so that was going to have to do the job for the time. I had always intended on going back and re-coding some new templates, but it never happened.

I am currently working on a project and we are horribly understaffed, and there's no relief in sight. There are some huge deadlines coming up, and it's time to make the rubber hit the road. I already code fast (and tight), but I needed to clone myself a couple times over to make the deadlines. So when the announcement came this week of CodeSmith 3.0, I decided I would take a new serious look at it and see what it could do for me.

Holy crap! In a matter of hours I had some pretty solid templates up and running, which will save the team many, many hours of redundant coding tasks in building this application. I have so many ideas for new templates it's scary, and I have only scratched the surface for what the tool can do. If you haven't looked at it yet, I recommend immediately going to CodeSmith and downloading a trial.

Tip of the day: Using Web Services in a Windows environment

Sat, 23 Apr 2005 20:36:27 GMT

If you are using DIME attachments, and you want to use them in a Windows client, this tip will save you some time. I created a File Upload/Download web service for a client I am currently working with, and until this week is was used solely on a web front end. However, there was a request for a Windows client, so I set out to create one using the same code.

All seemed well, until I went to compile. My Web Service is called FileService (for the purposes of this discussion), and in order the use DIME attachments after setting a web reference, you need to use the FileServiceWse version of the web reference (the wse class). The problem was, one wasn't generated in the proxy. I debated using the proxy for the web application, but then decided to try something a little different.

I removed the existing Web Reference, added a reference to System.Web to my project, then added the Web Reference again. Viola! My wse version was available now, and my code compiles! I decided to post this to save someone else a bit of time, as well as a reminder to myself in the future.

Error Handling Discussion

Thu, 14 Apr 2005 16:49:54 GMT

There's a lot of debate on the best type of error handling, where to log it (if at all), and when to do it. For example, here's a debate today:

http://weblogs.asp.net/alex_papadimoulis/archive/2005/03/29/396141.aspx

In this debate, the question is Return codes vs. Throwing an Exception. You can read the blog entry to see the debate. Here's my take, and why.

First, I always handle the exception where it happens, and rarely bubble it up. Why? First, what if the calling code doesn't handle the exception? Now you have an unhandled error, and it could cause an application to crash. On a recent project for a large chipmaking client, I got into this debate a few times with all levels of developers. It was always an interesting debate with senior developers because they at least adopted their belief into action and a bigger strategy. For example, they may trickle it up and handle it at the highest level, but if they forget to handle it, the best developers handle the uncaught errors at the thread level. The advantage is they have the error information and can use it to provide the user some feedback as to the nature of the problem.

But those are good developers, and I would say the top 10%. As an example, I had this debate with a mid-level developer who was convinced he was a senior level developer. Now, as I tell this story, let me mention I am a very good poker player. He adamantly felt errors should be bubbled up and handled at the UI. I countered him with the standard “What happens when the exception isn't handled?” He advised me he never forgets. Enter the poker player in me.

Being a consultant, you have to know when to shut up and let the “hand” play out. This was an XP project (never again), and as we paired, I watched him write some code, and I even reminded him about error handling. For the most part, with my diligence and because we had just had the discussion this guy was being fairly consistant in his exception handling at the UI level. However, I stopped reminding him (it's instinct for me to do it now), and sure enough, he forgot, and the application crashed a horrible death. The reason I wanted to have this discussion with him was because his code was causing about 80% of the crashes on the team, and I was trying to help him improve his skills (and our project). To finish the story, the guy's ego was so big he refused to accept responsibility for the crashes or even acknowledge that I had a valid point about forgetting error handling, and kept on his merry way.

Back to the point, IMHO error handling should be handled where the error occurs. This is especially true in multi-developer projects, as you cannot guarantee someone who calls your code is diligent enough to handle things when problems occur.

But that has a serious downside -- how do you let the user know there was a problem, and it was handled? The answer -- return values. OK, there's a little more to it than that. An error code is never enough information to provide feedback or to decide what to do when the caller receives notice an error occurred. Even worse, a number is useless in trying to relay relevant info to the end-user.

What I have adopted is this: I have a base class which my other classes inherit from. In that class, I have an ErrorMessage property (string) which is set where the error occurs, or in a central error handler. When a method encounters an error, it returns an integer value indicating failure. The calling routine (if desired) can check the ErrorMessage property and use that value for displaying a message or get details as to the nature of the problem. It can also ignore it if it wants. The key thing though is that the error will never go unhandled and cause the application to crash.

I'll be happy to post up some examples if there is interest. This is just a very important topic to me, and one I think which separates the wheat from the chaff, as they say!

In the debate listed above, there's an argument over performance. There's a balance here: you need to perform well, but performance is killed when the application crashes. Find a solution which is robust but also performs. Not handling an exception is not an option for robustness.

Tip of the Day - My errors aren't showing up in the task list..???

Mon, 04 Apr 2005 18:28:35 GMT

I have a large ASP.Net project I am working on, and the solution contains about 6 projects. Periodically, it won't compile, but when I look in the Task List there are no errors listed. After a lot of trial and error, I finally found a solution which restores the missing error notations, so that I can fix the problem and move on.

Right-click in the “Task” screen, and select the “Show Tasks/Comments” option. Try compiling, and of course it will fail again. Then, right-click on the “Task” screen again, and select the “Build Errors” option, and they should appear. It seems to work fairly consistantly so I think this “workaround” may actually work.

As an alternative (although not as easy to work with), you can just look at the output window, and filter through the text output. Take your pick, you should be able to see what the problem is!

ADDENDUM: It happened again, and these steps didn't work exactly. To make it work, try to compile again between “right-clicks” and they should appear.

How to get the technical interview....(Part III?)

Mon, 21 Mar 2005 15:11:00 GMT

Let's talk resume's for a minute. You want that interview don't you? Well, sometimes all you have to get you there is your resume (although personal reference is the best way if you can get it, an area where networking and doing quality work can help).

There's a million places on the internet to help you decide how to structure your resume. I have only gotten one criticizm from my resume, and I am not sure if it's the content or the structure which works best. But here's a couple of pointers which I think have helped out my resume.

Place a logo of any certifications you have if available (e.g. MCSD). These are real eye catchers. Make the images small though..
Place your specific skills separate from your experience, preferably near the top. This makes it easy to survive the first pass from the recruiter/manager.
Sell yourself! Research “power“ words and make any experience descriptions short and chock full of those words.

Now, there's a few easy tips of what to do. I have been helping staff for years, and here's some of the gems I have seen.

Horrible writing and spelling.
Obviously exagerated skills and experiences (4 years experience, 10 years at a certain skill)
Never say you are an expert at anything, even if you are. Humility goes a long way, and if the interviewer knows more, you'll be humbled by them, as I witnessed in the past week.
Use nice paper if submitting a hardcopy (I received one handwritten on a partial piece of paper -- I kid you not)

It's not tough... just use some common sense!

Things not to do on a technical interview.. -- Part II

Sat, 19 Mar 2005 00:14:50 GMT

OK, so let's assume you get past the technical part of the interview. Play you cards right, and it's not hard to do. You've managed to show you have a decent personality (which is VERY important in interviewing), and you think you have a good shot at landing the job. That's where we were with a couple of candidates in this interviewing session. However, the strongest candidates managed to snatch defeat out of the jaws of victory, and blow their chances at getting the job. How?

In one case, a person was interviewed who, shall we say for legal reasons, is in a protected class of employment law. The interview was fairly strong, and he had a great shot at getting the job. However, when we asked this person if they had any questions, the first thing out of their mouth dealt with their protected status, and almost a “veiled“ insinuation we needed to be make sure we didn't take that into consideration. Up until that point, we hadn't even thought about it. However, it came clear that there was the potential for legal issues should this person become an employee.

In another case, the prospect was extremely strong. I had given my thumbs up almost wholeheartedly until we once again asked if they had any questions for us. It's always a good idea to ask for some feedback from your interviewers, and even lightly use a closing technique to get the interviewers to think you'd be right for the job. However, this prospect put each and every one of us on the spot requesting specific feedback for their interview. And I mean very direct, pointed and almost intimidating questions (I don't get intimidated, I just thought it was rude).

After the inquisition, he made this bold statement “Since there doesn't appear to be any resistance or negative feedback, I think you should just go ahead and make the offer.“ WTF?!?!? Well, it was politely stated that we had other candidates to consider, and we would be in touch soon.

This same candidate took it upon himself to continue the pressing over the next couple of days. He managed to obtain all of our individual email addresses, and send communications reiterating we should “choose“ him, like we were voting a tribe member out of Survivor or something.

Don't get me wrong, it's good to send thank you notes, and it's good to gently ask for feedback and sell yourself. Putting people on the spot is ABSOLUTELY not the way to do it though. Repeated unsolicited communication and badgering is also not a great way to get people to remember you positively after the interview. Say thanks, ingratiate yourself for allowing them to consider you, and get out.

You can also blow it in one question. When one candidate was asked what he liked to do in his spare time, his answer was “Anything dangerous.“ Great, an insurance risk! One guy mentioned he sleeps with his computer. Scary.

I might do a part three about resumes. I have a tale about a cocktail napkin, and a guy who claims to have invented the internet, but I guess I will save that for part III.

Tip of the Day: Testing WSE2 (SOAP) DIME Attachments and the 'ResponseSoapContext.Current is null' issue

Fri, 18 Mar 2005 21:15:58 GMT

I am so irritated at how poor the documentation for WSE2 and DIME attachment processing is. So today's tip will save someone new to the process countless amount of time. Here's the scenario: You want to process a file download using DIME attachments. You write your web service, and want to test it. You run the web service, pop up the Visual Studio test page for the web service, and it doesn't download your file as expected.

So, you start debugging, and it turns out the ResponseSoapContext.Current is null. WTF? It *should* work. So you grab all your books and online articles you can find, and a few people are having this problem, but no one seems to post how they solved it. Well, after spending a few hours trying to solve the problem, I run across a blurb that states you can't test your DIME downloading from the web page which is created by the Visual Studio IDE, you *have* to create a separate client (those weren't the exact words, but that's the gist of it).

Arrggh!!! Wasted time! But if I can save someone else from the same frustration, I will.

Good luck!

Things not to do on a technical interview.. -- Part I

Thu, 17 Mar 2005 20:19:01 GMT

I wear many hats on the projects I work on, from developer to mentor to pure consultant. One of my current clients is having me help make staffing decisions by performing technical interviews on potential candidates.

I've helped out with this kind of thing before, and I want to make some comments because I have noticed a lot of trends in technical interviews. I'll also have some comments on the interviewees, and how you can talk yourself out of a job over and over again. To put this all in context, let me just say in the past 10 years as an independent consultant, I have never had a day of bench time. Also, in the many, many interviews and initial meetings I have been to, I was only not given the project one time, and that was quite mutual by the end of the meeting. Some day, I will write about that particular experience, and in an unusual change of things, I am going to name names of the guilty to save others the same problem.

First, the concept of the technical interview. I have seen post after post of technical questions to help identify the level of technical experience a candidate has. It's amazing how specific those questions are. Why? They really don't need to be. From my experience, when someone is asking those excruciatingly detailed questions, it's more for the interviewer to feel superior than the interviewee (a warning sign for you job hunters) than to ascertain a knowledge level.

It's not practical or informative to ask deeply detailed technical questions. Why? Programming is like medicine in that it's highly specialized at times. I was asked some specific details about the DataAdapter one time, and I couldn't answer it. Does that make me a bad hire? Most people wouldn't think so, but I wrapped the functionality into a data access class, and I don't have to worry about the implementation ever again unless I need to do something specific.

As an interviewee, it's important to worry less about the answer to that type of question than to address how you'd solve the problem. In the DataAdapter above, I stressed I employed the OOP concept of encapsulation, and if I need to know a specific implementation, I grab Google or the MSDN and solve the problem. The key is this: if you don't know the answer, be truthful about it (and why), and how you would solve the problem.

You can really identify a programmer's level of expertise with simple questions. For example, I ask something like “What's the difference between an abstract class and an interface?” Not terribly tough, but you can tell from the detail of the answer a lot, both about their programming style as well as their level of knowledge.

I ask two sets of technical questions. The first are the the purely technical questions (about 10), and then seven or eight “philosophy” questions. I plainly state there are no right or wrong answers, but I just want to see what level of thought they place into their development. Here's an example:

Describe some exception handling you've implemented, and the advantages and disadvantages you encountered with that method.

Not too bad, right? But what does it tell us? It tells me how robust of an application this developer is capable of writing. From these interviews I have been participating in, I would say 80% of the candidates say “I just log to a file.” without any reason why or “try..catch”. All you need here is an answer and a conviction. But with the low quality of either portion, I know handling the problems in an application are not a real priority, which also tells me the developer does not code defensively. Things like validation and good user dialogs will likely be missed too. While these things may not be important in your organization or project, it may also mean they are not the most diligent programmers.

This ends the question section of this topic. In the next part, I will descibe how I watch a couple of top candidates snatch defeat out of the jaws of victory!

Tip of the day: Renaming files with a time date stamp

Wed, 16 Mar 2005 15:26:57 GMT

Sometimes as a developer you need to rename a file with a date time aspect so you can do something like guarantee uniqueness, track submission information, etc. There's always a ton of ways to do this, but I decided to write a couple of routines to do this using the FileInfo class. First, the code:

/// <summary>

/// Gets a string you
can append in a file name to supply uniqueness

/// </summary>

/// <returns>a
string which looks similar to 2232005_090812 which is a date time</returns>

public static string GetUniqueFileNameIdentifier()

{

    return DateTime.Now.Month.ToString()
+ DateTime.Now.Day.ToString() + DateTime.Now.Year.ToString()+ "_" + DateTime.Now.Hour.ToString()
+ DateTime.Now.Minute.ToString() + DateTime.Now.Second.ToString();

}

/// <summary>

/// Renames a file with
a unique identifier in it

/// </summary>

/// <param
name="fileName">file name to rename..</param>

/// <returns>unique
name of file with datetime identifier in the name. e.g. MyFile.txt renamed to MyFile_2232005_090812.txt </returns>

public static string FormatUniqueFileName(string fileName)

{

    FileInfo fi = new FileInfo(fileName);

    return fi.Name.Replace(fi.Extension,"")
+ "_" + GetUniqueFileNameIdentifier() + fi.Extension;

}

First, the FormatUniqueFileName funtion takes a file name (like test.txt), and inserts the date time info (in the current format, it does this as fileprefix_mmddyyyy_hhmmss.fileextension, so in our example, we might get test_03162005_071525.txt.

Not a real complex function by any means, but one that's reused a lot in development, and I decided to get this out just in case some developer wanted to save 5 minutes!

Enjoy!

Tip of the Day -- Using GetDate in functions

Fri, 11 Mar 2005 21:45:00 GMT

Someone asked me today if I knew that you couldn't use GETDATE() in functions in SQL Server. Well, I did, so I dug out this solution I had found a while back, and decided to post it, since I am sure others have come across the same issue.

Basically, you use a view to do the work for you... here you go!

CREATE VIEW Function_Assist_GETDATE

/********************************************************
*
* A view to return one row, with one column, the current
* date/time from the built-in function GETDATE(). This
* view allows a UDF to bypass the restriction on access to
* the non-deterministic getdate() function.
*
* Attribution: Based on a newsgroup posting in by Mikhail
* Berlyant in microsoft.public.sqlserver.programming
*
* Common Usage:
DECLARE @dtVar datetime
select @dtVAr = [GetDate] from Function_Assist_GETDATE
**********************************************************/

AS
SELECT getdate() as [GetDate]

GRANT SELECT on Function_Assist_GETDATE to PUBLIC
GO

Tip of the Day -- Great Exception Handling article

Wed, 09 Mar 2005 17:47:50 GMT

I am currently trying to go through a Code Review at a large bank to get our code approved for release on the internet. One thing that came up was in some situations, we are displaying the raw exception message which was listed as a no-no, which I disagree with. While it's not particularly informative to the user which is potentially an issue, I can't see where “Invalid use of null” is going to be particularly useful to a hacker, but to a developer, that tidbit may help identify the problem when the user calls for help (good application logging aside in this example). Ironically, when errors weren't handled because the developer forgot, this passed code review.

So my intent was to enumerate all the default error messages to determine if there are any which would be particularly helpful to a hacker. While I am still looking to find or create an application which will enumerate all the default messages that .New throws out, I did come across a great article which lists the various error handling philosophies, and tries to weigh out the pros and cons of each. Here's where to get this pearl of wisdom:

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnbda/html/exceptdotnet.asp

Where did the posts go?

Thu, 03 Mar 2005 23:07:53 GMT

I must be getting some hits on this site according to my referrals, but I am sure it could be a ton more if I posted more. So, why haven't I been posting the tips of the day?

Well, they are going to be starting up again soon. I had to deliver 2 projects suddenly, and pretty much all my waking hours were dedicated to actual work which brings in cold-hard cash. So now I am officially down from 3 active projects to one full-time project, so I should have some time to make some postings.

In that time, I have created a SOAP-based web service using DIME attachments, encryption and compression, used a horrible product called Syncfusion for Excel manipulation, developed invoicing PDF generation using DynamicPDF, written a Windows service, written a Windows application, developed to “rough stuff” inner workings of 2 ASP.Net web sites, and put some enhancements on a VB6 program I originally developed 8 years ago (in VB4 originally -- talk about longevity!). Been a busy year so far!

I also won a fairly large poker tournament in a local casino, and have a shot for a satellite seat for the World Series of Poker.

But things are starting to slow down a bit, so start looking for more tips of the day for things I have learned since the year began!

The difference between @@IDENTITY, SCOPE_IDENTITY(), and IDENT_CURRENT()

Fri, 31 Dec 2004 15:25:39 GMT

So, you want to get the value of an identity column after an insert so you can update the UI or use it in another procedure. You've been using @@IDENTITY for ages, and it has worked fine. But today, you're getting a new value. What's up?

There are 3 (or more if you want to consider queries or identity tables) methods for getting the identity value from a table after an insert. The methods are @@IDENTITY, SCOPE_IDENTITY() and IDENT_CURRENT(). What's the difference?

@@IDENTITY gets the last inserted identity value. The problem is, in a high-volumn environment or one with triggers, it may not be the value you are expecting.

The SCOPE_IDENTITY() function gets the last identity inserted within the same scope (e.g. inside the procedure you're running). This is useful especially when your table has triggers which might do another insert. You'll only get the identity value of your change, not the trigger's.

The IDENT_CURRENT('table_name') returns the last identity value for the specified table, regardless of scope.

So, for safety in your routines, if you want the value YOU inserted, try the SCOPE_IDENTITY function for safety!

Finding all tables where a field exists in SQL Server

Thu, 30 Dec 2004 18:09:49 GMT

Here's a quick and dirty routine I use all the time. This simple procedure will list all tables in your database where a particular field is found. Not earth shattering by any means, but useful and since I find I use it all the time, I thought someone else might find it userful and same them the brief effort to write their own!

IF EXISTS(SELECT name FROM sysobjects WHERE name = 'sp_findField' AND type='P')
BEGIN
DROP PROCEDURE sp_findField
END
GO

CREATE PROCEDURE dbo.sp_findField (@fieldName varchar(100))
AS
BEGIN
SET NOCOUNT ON

SELECT so.name
FROM sysobjects so, syscolumns sc
WHERE so.id = sc.id
AND sc.name = @fieldName
ORDER BY so.name

END
GO

GRANT EXECUTE ON sp_findField TO public
GO

Tip of the Day: Formatting Dates

Tue, 28 Dec 2004 17:07:14 GMT

Here's another simple tip, but it does encapsulate some of the functionality needed to format a DateTime (or a string) to a particular string format. First, from the documentation, here's some examples of the DateTime formatting:

Column 1: Format String, Column 2: The format of the date
    ' d :08/17/2000
    ' D :Thursday, August 17, 2000
    ' f :Thursday, August 17, 2000 16:32
    ' F :Thursday, August 17, 2000 16:32:32
    ' g :08/17/2000 16:32
    ' G :08/17/2000 16:32:32
    ' m :August 17
    ' r :Thu, 17 Aug 2000 23:32:32 GMT
    ' s :2000-08-17T16:32:32
    ' t :16:32
    ' T :16:32:32
    ' u :2000-08-17 23:32:32Z
    ' U :Thursday, August 17, 2000 23:32:32
    ' y :August, 2000
    ' dddd, MMMM dd yyyy :Thursday, August 17 2000
    ' ddd, MMM d "'"yy :Thu, Aug 17 '00
    ' dddd, MMMM dd :Thursday, August 17
    ' M/yy :8/00
    ' dd-MM-yy :17-08-00

First, we'll need a function to verify the string we have is a valid date.

   
    public static bool ValidDate(string checkDate)

        {

            try

            {

                DateTime
dtTemp;

                dtTemp
= DateTime.Parse(checkDate);

                return true;

            }

            catch

            {

                return false;

            }

        }

The ValidDate function takes a string, and returns true if the value is a valid date, or false if it isn't.

Next, here's the function for formatting the date:

public static string FormatDateTimeCustom(string valDate, string formatString)

{

    if (ValidDate(valDate))

        return Convert.ToDateTime(valDate).ToString(formatString);

    else

        return valDate;

}

valDate = the string to format

formatString = the format style as listed earlier

That's it for today!

Tip of the Day: Determining which control caused the Postback

Mon, 27 Dec 2004 22:19:36 GMT

While not 100%, you can look at the following to see what control caused the postback on a form:

Request.Form("__EVENTTARGET")

It works because ASP.Net uses javascript to handle the postback functionality, and the __EVENTTARGET query string value can contain the name of the control which caused the postback.

Want to know what arguments are being passed during the postback? Take a look at the Request.Form(”__EVENTARGUMENT”) value!

Tip of the Day: Debugging Javascript in ASP.Net

Tue, 21 Dec 2004 21:26:19 GMT

I don't think you can be a real effective ASP.Net programmer (personal opinion alert) unless you can do SOME javascript. Postbacks not only increase your server load, they can also detract from your user's experience on your ASP.Net site.

The downside is that working with javascript is that it's always been tough to debug (if not impossible), as well as untyped, but that part's an aside. Well, it's tough no more. Here's today's tip(s). First, enabling debugging:

Open your browser, open the Tools menu, and select the Internet Options menu item.
On the Advanced tab, locate the Browser section, and uncheck “Disable Script Debugging“ (see image below).
When you fire up the ASP.Net debugger (either manually or by default), make sure the “Client Script“ option is selected.
Trigger the javascript.

Image 1: Browser Options

Image 2: Setting the script debugging in the Process Debugging command in .Net

OK, you're all set for debugging. So what! Well, the thing I learned today was how to break into the script (without an error, which causes it to trigger debugging automatically) is to add the following script where you want to break:

debugger;

Your web page will break right there, and you'll be able to step through it just like you would your normal ASP.Net page, with local variable browsing and everything!

Implementing the Split function in C#

Mon, 20 Dec 2004 21:13:55 GMT

Say what you will about VB, it does have some wrappers for some neat functions. One of my favorites is the Split function. Essentially, it takes a string, a parse character parameter, and returns a string array of the items. For example, it might look like string[] mystring = Split(myCommaDelimitedString,”,”);

So here's what the code looks like:

  /// <summary>
  /// Replacement in C# of the VB.Net split function
  /// </summary>
  /// <param name="baseString">string to parse</param>
  /// <param name="splitChar">chanracter to parse with </param>
  /// <returns></returns>
  public static string[] Split(string baseString, string splitChar)
  {
   char[] sep = {(splitChar.ToCharArray())[0]};
   return baseString.Split(sep);
  }

Now, I know you can use the string object's split functionality to do the same thing. However, those coming out of the VB world will appreciate the encapsulation, as well as never having to remember the syntax for pre-defining a character array.

Tip of the day - Javascript - Getting the control which called a function

Sat, 18 Dec 2004 21:55:17 GMT

One of the things I use this blog for is to keep track of tips which I may need while out at the client site. I have a fairly extensive CodeLib library I use, but for some reason, I didn't have this in my library.

If you're new to javascript, which I am definitely still in the learning stages of, at some point you are going to access the control which called a function. I did a few searches, and it turns out, unless you know what you are looking for, it's tough to do a search like “javascript determining control which called a function” and similar searches. So here goes, and hopefully this simple tip will save another developer a little time. It IS a basic function, I will be the first to admit, but it is also useful to know for an ASP.Net developer. And the code is:

document.activeElement

There you go! Simple, but for some reason, it's assumed you should know it, which to a degree, I agree with. But I would also have to say online there seems to be an assumption that everyone already knows the DOM!

Skipping over a routine automatically in the debugger, and other neat debugger tricks..

Wed, 15 Dec 2004 20:15:13 GMT

Do you have a routine which you know works, and you don't want to have to step into when you're debugging? Granted, you could you the hotkeys to do it, but why bother? The System.Diagnostics namespace provides some neat functionality for helping you in your debugging process. Here's some examples:

//This attribute prevents the debugger from entering, as well as no breakpoints within

<System.Diagnostics.DebuggerStepThrough()>

private string MyRoutine()

{

//Don't step through this

}

I am actually not sure what the difference between that and the DebuggerHidden() attribute is though. The description in the help is the same. Anyone know?

Tip of the Day: The Importance of Defragging your SQL Server drive

Sat, 11 Dec 2004 18:29:51 GMT

I am a huge fan of SQL Server. Don't get me wrong, there's nothing wrong with Oracle per se, other than it's tough to get it to run right and efficiently, and not for the amateur. If I was considering cross-platform work, Oracle would be the choice for me. For everything else, there's SQL Server, and when the next version comes out, look out!

But one “downfall” of SQL Server is that it becomes very easy to believe you can administer a production database with only Access skills, or worse, none at all. Some stories come to mind from my experiences.

First, I was doing a project for a large state agency, and at the time no one but the DBA could touch the SQL Server, or directly run script against the production server. I needed a very simple update script run, so I wrote it out, and gave it to the “DBA” to execute. He returns in about 5 minutes and tells me it doesn't run, and asked if I would mind taking a look at it. I did, and I had accidentally pasted two “set” keywords in a row. Even a Jr. Developer with a minutia of SQL experience should have seen this and been able to fix it. So, I fix it, and I asked him why he didn't just erase the extra “set”. is reply: I don't know SQL. Please keep it quiet.

Mind you, this guy was touted as a Sr. DBA, and responsible for about 16 databases which control some very important data. Unfortunately, this wasn't the worst of it.

One day I was using the restroom (that's important to the story), and he comes in and begins using the stall next to me. We begin some general chit-chat, and he's excited he can tell me something about SQL I might not know. His epiphany? “I went to a class, and we learned about indexes in it! I am so excited to start trying them out!” Well, since we had never been able to directly access the database, I had just solved some of our performance problems. I also got access to the databases from that day forward..

Another performance story. I was doing a project for an Internet startup, and I overheard they were having some SQL Server performance problems. The sign-ups for their site was killing their SQL Server with all the activity. I offered to take a look at it, but there was a definite anti-Microsoft spin at the company, and they were going to switch to Oracle because the owner had been told it was simply because Microsoft can't keep up with Oracle. I was working on a VB application for them, so they assumed wrongly that I didn't know databases very well.

So, they hire a team of Oracle (weren't employees of the Oracle Corp, just for reference) developers, and in 4 months and almost $300,000 later, it still wasn't up and running. The owner was bleeding cash, and was pressing the Oracle team to find out when the database conversion would be done and the bleeding would stop. They then informed him it would be about another month (and $100K), but even then they'd need to keep one of them one to maintain the database, or hire a full time Oracle DBA.

So I re-enter the SQL Server discussion with the owner. I ask him to let me look at the SQL Server configuration, and maybe I can buy him some time until the Oracle system is ready to go. Immediately, I see there are no indexes on the tables, and the stored procedures were very inefficient. By adding indexes alone, the performance gain alone went from ~98% resources used on the server (processor and memory) to less than 5% peak usage. The Oracle team was gone the next day (sorry guys), and the SQL Server portion ran flawlessly from that day on. But something so simple cost over $300K and wasted four months, and probably cost the company a lot of lost business.

My point is this: SQL Server is simple to use, but you have to educate yourself on how to use it best, because in some ways it makes it way too easy to think you are doing the right thing, when in fact it can have a huge impact on your performance. Next thing you know, you think the server can't handle it and you're out $20K on a new server which you don't need.

Case in point: I was hired by a bank to help a team of new developer's get up to speed in VB.Net and ASP.Net (I tried to get them to go C#, but that's another story). Their application was simple, but every day the resources on the server(s) were getting pegged and the entire system was unusable until the next reboot.

I decided looking into this would need to be a top priority. I checked the indexes, and they all looked good, but we did some tweaking there, and the problem was still occurring. I finally pull out the SQL Performance Analyzer, and quickly nail down there is a serious disk I/O problem. For example, I pull out a small table of about 200 rows, and do a select *, and it turns out it take 3000 disk I/O's to get it. The indexes were fine, and the record size was small, so there was something else going on.

On a hunch, I check to see if the disk drive is fragmented. Holy crap! It looked as if it had never been defragged, and come to find out, it hadn't. The network admin responsible for this production machine advised me the way he builds the machines means that they never have to be defragged. So I show him an image of the fragmentation on the drives, and he thinks I rigged it. End of conversation with him.

So I fix the problem, then ask for $200 for a program to schedule the de-fragmentation automatically. I don't get it, so I now have to manually defrag it once per week. Cost? Well, for me to track it down, and the time spent every week over a year and a half? Likely over $5000. Go figure.

I tried to get the employees there to take responsibility for doing it, but it never seemed to be a priority for them. So when I left to being a new project, I reminded them someone needed to do it. Well, I can assume for a while someone did. But I am back there, and yesterday there were complaints of poor performance. And guess what I found when I checked? The drives were very fragmented. One is so full and so bad, I think we're going to have to drop all the indexes, defragment, then rebuild them. That's gonna cost a ton of time and money. The $200 is going to be budgeted this time.

The tip: Make sure you keep your SQL Server data and index drives defragmented. Failure to do so can have a huge impact on your SQL Performance, since in the end, SQL Server relies on quick disk I/O to perform well.

-- Daryl

Some great free tools for ASP.Net

Fri, 10 Dec 2004 02:30:27 GMT

I was out late last night in my first “real” poker tournament, so I am a bit too tired to whip out some good code. (I did OK at the tournament, and hit my target, just as an FYI). So tonight's tip is going to be about a great set of free components I use occasionally in ASP.Net. And at least for this one, you can get the source at a very reasonable price. Check these out:

Excentrics World

They have a great collapsible panel, masked textbox, breadcrumb tracker and a popup calendar, plus a few others. Definitely worth looking, and throw him a bone and buy the source!

More cool tools I have found if I can stay awake!

-- Daryl

Tip of the Day: Dynamically boxing a type in C#

Wed, 08 Dec 2004 14:49:20 GMT

Here's a quick tip for casting to a particular type if you have the name of the type. Once again, it may be obvious to some, but if you've never done it, it's tough to find a quick example of it, so here goes.

I was implementing a custom ViewState for an UserControl I was creating, and came across a situation where I needed to dynamically box a type, when all I know is the type which I have stored in a string. I am creating a special container control which can host any other type of control, and for restoring ViewState, I needed to cast it correctly when restored. Fortunately, I followed a hunch, and came across the answer -- System.Type.GetType.

string testType = “System.Int32“;

Type myType1 = Type.GetType(testType);

Not Earth shattering, but then again, you have to know where to look!

Castastrophic Error -- What to do when you see this when trying to debug..

Mon, 06 Dec 2004 04:44:29 GMT

OK, so you're looking at some really obscure code, so it's time to step in and see exactly what it's doing, and the best way to do it is use the debugger. Actually, if I have to give you a reason to use the debugger, you probably shouldn't be reading this in the first place. You fire up the VS IDE, hit F5, and viola! You see the following scary message:

What the heck? “Error when typing to run project: Unable to start debugging on the web server. Catastrophic failure.”

Likely you won't see this unless you don't have Admin privledges on the box. Right now, I am doing a project for a large bank, and trying to get rights to do anything is like trying to pry a “Magic” card from a freshman engineering student. My rights are so messed up, I actually have to do the following steps at the start of every day I plan on debugging. If you see this message, here's the steps you can try to get rid of it and get on with your debugging.

First, you're going to need to change one of the local security policies. Open up your admin folder, and select Local Security Policies. You should see something similar to the image below. Next, select User Rights Assignment.

Locate Impersonate a client after authentication, and double click on it. You should get a dialog similar to the following. What you'll need to do is add the IWAM_ (and I add the ASP.Net worker thread just for good measure to the policy) like below. For the record, I believe only IWAM_ is required.

OK, you've taken the first step to fixing the problem, but that's not it. You've got to get IIS and the rest of the system to recognize the new policy. So, first, open up the “Run “ command from the Start menu) or command prompt, and type the following:

Type

secedit /refreshpolicy machine_policy /enforce

This will refresh the security policy for the local machine. Next, type this command to restart IIS now that everything is set.

iisreset

That's it! Assuming the IIS application workspace is set to allow debugging, and everything else is good on the machine, hopefully you'll be debugging like the Orkin man!

-- Daryl

Too cool for words!

Fri, 03 Dec 2004 03:23:38 GMT

The winner of the cool application for the Tablet PC was announced, and the top prize winner was an application called ArtRage. Holy cow! I am no artist but this thing is cool. Although you can use it with a mouse, if you hae a Tablet PC, the play factor alone on this is worth the download. Best of all, it's free.

My favorite part: the trace feature. Essentially, it allows you to place a picture in the background, trace over what you want, then save the tracing (without the picture in the background). I may become an artist yet!

For all the apps (which I am sure to check out!) check the contest out here:

http://www.microsoft.com/presspass/press/2004/dec04/12-01TabletPCWinnerPR.asp

or go right to the site at:

http://www.ambientdesign.com/artrage.html

Here's a weak sample:

Notice the brush textures of the paintbrush....

-- Daryl

WinCV revisited...

Thu, 02 Dec 2004 05:42:28 GMT

Someone on the project I am currently working on stumbled on some documentation for WinCV, and in that documentation, it tells you how to add Assemblies which aren't in the GAC. Here's the link from the MSDN, and then I will point out the interesting part:

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cptools/html/cpconwindowsformsclassviewerwincvexe.asp

By using a response file, you can issue the necessary the parameters to look at one or more files. From the documentation:

The following code shows the contents of a response file myFile.rsp. Using a response file eliminates the need to individually type the commands at the command prompt.

/r:myAssembly.dll /r:myOtherAssembly.dll

The following command reads the response file myFile.rsp and executes the commands specified in the file.

wincv @myFile.rsp

So,
you could set up a standard response file which holds all the names of assemblies
to search!

Pretty neat!

Tip of the Day: Retrieving an enum's value by text, and text by value

Tue, 30 Nov 2004 05:11:10 GMT

Here's another tip which is a wrapper to retrieve the value from an enum by it's text and also to get the text of an enum based on a value.

public static string RetrieveEnumTextByValue
(Type enumType, Object value)

    if (enumType.IsEnum)

        if (System.Enum.GetName(enumType,value)
!= null)

            return System.Enum.GetName(enumType,
value);

    return "";

public static int RetrieveEnumValueByText(Type
enumType, string text)

    if (enumType.IsEnum)

        if (System.Enum.Parse(enumType,text)
!= null)

            return Convert.ToInt32(System.Enum.Parse(enumType,
text));

    return -1;

I'm a little lazy tonight, but maybe I will come in later and post usage. I'll make a better effort to do that in the future, but I have to be up in a few hours, and being tired tomorrow just won't do!

-- Daryl

Tip of the Day: Simulating the CHAR function in C#

Tue, 30 Nov 2004 05:05:16 GMT

Yet another tip of the day. I guess until I get an environment set up to go over my Filter Component I will be posting a lot of tips just so I keep the blog active. Be patient, it will be worth it when I get the project set up.

CHAR() was a useful function for taking an integer value and returning the Ascii equivalent from the value. There's a bit more to it in .Net, so here's a C# wrapper function to do the same. Once again, there's no error handling or validation, so if this is important to you (and it should be), caveat emptor.

public static string Char(int asciiCode)

    Byte[] charBytes = {asciiCode};

    return System.Text.Encoding.ASCII.GetString(charBytes);

Enjoy!

-- Daryl

Tip of the Day: Sending Ctrl-Alt-Delete through a Terminal Services Client

Mon, 29 Nov 2004 18:16:26 GMT

It took me a few minutes to find, so I wanted to blog on it just so I could find it again, and anyone out there can use too. I am currently working in a wierd development environment which uses Novell over an NT network. So I have two passwords, and the only way I can change the NT password is through Outlook or using Terminal Services to go to an all NT machine and do it. Outlook wasn't working, so I went route #2.

In order to send the Ctrl-Alt-Delete sequence in Terminal Services, I had to use Ctrl-Alt-End... Go figure!

Tip of the Day: Speeding up your typing and Intellisense

Mon, 29 Nov 2004 16:36:57 GMT

This is a pretty simple tip (or set of tips) but one in which if you don't know, you're going to be glad to find them out.

First, depending on how your profile is set up in Visual Studio, you can type Ctrl-space to get the Intellisense to come up. If there's only one possible option, it will go ahead and type the rest out for you. For example, type “Sy” in the Code behind editor, and press Ctrl-space. You should see a ton of “System” options you can select from to complete the word.

OK, that was easy, right? Well, here's a little one which is often overlooked: creating an alias in your using statement.

Typically, you might set up your “includes” as follows (in C#).

using System.XML;

That works great if you are really familiar with the object model, and know what public method/member you want. Suppose you don't? You can do this:

using MyXML=System.XML;

Now, when you type MyXML, you can get the full Intellisense for the System.XML without having to type all that (or guess). Simple, but great for working with new workspaces.

Tip of the Day: Converting an integer to a Roman Numeral in C#

Sat, 27 Nov 2004 04:25:01 GMT

Not sure where I got this, so my apologies to the original author, but it's been a pretty useful function. Of course, you might want to wrap this with some error handling and validation code, but here's a good start for you...

private string GetRomanNumber(int number)

    string[]
ArabicNums = new string[] {"1", "4", "5", "9", "10", "40", "50", "90", "100", "400", "500", "900", "1000"};

    string[]
RomanNums = new string[] {"I","IV","V","IX","X","XL","L","XC","C","CD","D","CM","M"};

    int ArabicUpper
= ArabicNums.GetUpperBound(0);

    int ArabicLower
= ArabicNums.GetLowerBound(0);

    string Output
= "";

    for (int i
= ArabicUpper; i >= ArabicLower; i--)

        while (number
>= Convert.ToInt32(ArabicNums[i]))

            number -= Convert.ToInt32(ArabicNums[i]);

            Output += RomanNums[i];

    return Output;

Enjoy!

Reading, Reading, Reading....

Thu, 25 Nov 2004 05:51:47 GMT

I seem to go in spurts in honing my technical skills by reading. Lately, I have been on an uber-quest to learn new things through reading, so I thought I'd write a bit on one I have finished, and the next likely target. My .Net and SQL Server library is pretty stocked, with about 60+ current books on a variety of subjects from graphics to SQL optimization to network programming to UI ideas. Most just end up being references, but a few (like Rocky Lohtka's CSLA books) get the full study and learn act.

I just finished Open Source .NET Development : Programming with NAnt, NUnit, NDoc, and More By Brian Nantz. It's a good intro book if you want to get a real high level look at the open source tools for automating builds and automated testing. It's a little confusing if you're trying to learn what some of the tools do and which are best for which scenario, but it does give a good glance on nAnt in particular. I would recommend this book for someone wanting to understand what tools are available, but don't look for this book to get you results in really complex situations. Sort of a road map, but you'll still be looking for topos when you figure out where you want to go.

Looking ahead, I had just purchased Seeing Data : Designing User Interfaces for Database Systems Using .NET by Rebecca M. Riordan. It came in this afternoon, and I was very excited to get it on a long weekend where I can try to pump through it. I am a little dis-enchanted though, as it appears to be oriented towards Rich Clients. I do rich client apps, but I was looking more forward to ASP.Net suggestions. I haven't given up hope on that yet, but if there is limited information on web applications in the book, I would certainly wish they would put "rich client" in the book description. I'll give it a read and put an update here once I know for sure.

It's important to me primarily because I can make a program do twists through hoops with no problem. I can also make a program very usable in terms of functionality. But making it look pretty, it takes me a lot of time, and I never am happy with it. Note there is a huge difference between pretty and usability, although the two can work together quite well and create a symbiotic relationship.

That's it for now. I plan on posting a few more tips this weekend, and eating some good home-cooked food. So, all those so celebrating, have a Happy Thanksgiving!

-- Daryl

Test Driven Development (Test First) -- is it everything it's supposed to be?

Wed, 24 Nov 2004 04:10:05 GMT

I spent the past 11 months (as I mentioned previously) as part of a team of developers on an 'agile' project, using the Extreme Programming methodology. As I was working out today, I was reading the December 2004 issue of asp.net Pro magazine. The featured article is about Test Driven Development (TDD), and it's place in agile development.

First, let me preface this topic by saying I am absolutely FOR Test Driven Development. In my opinion, there's too little focus given by developers on focusing in what can go wrong with an application -- testing, error handling, malicious users, and a myriad of other potential gotchas. The purpose of this blog is simply to provide some alternative views on TDD, and some potential pitfalls, since there is little seen on the topic, especially from those of us in the trenches. Combine this in your approach to TDD, and you'll have a much better experience.

Here's an executive summery of the caveats to TDD from my experience:

No code is supposed to be written before the tests. Design first, then write the tests, or you'll end up with a bad design.
When tests take longer to write and modify than the actual coding, the process gets in the way.
TDD gives way to the erroneous philosophy that if your automated tests work, that's all the testing you need (except user acceptance).
There is the dangerous thinking that you can write automated tests to cover every scenario. See point 2 again.
There becomes a belief that the number of tests somehow correlates to the quality of testing, or the the mere existence of an automated test provides a better application.
UI testing tools (especially the open source varieties) are lacking in the ability to generate UI tests, at least from the web perspective in the trench I sat in.
When you data shunt the data access (and manipulation) portion of a class, that's not a very valid test. The database MUST be tested, and your tests must accurately reflect how the users are going to be actually using your objects for TDD to be of any use.

Let's look at each point in a bit of detail, so I can provide some details on my OPINIONS here...

First, the statement is made no code should be written before the test. OK, what exactly are you going to be testing for? For example, let's say you might be wanting to test customer creation. You envision the routine you want to test to return an integer which ties to the ID the database generates. OK, great! But guess what, that's a DESIGN DECISION. Why not set a read-only property of a class, and return a standard return code? Are you going to follow this exact style with the rest of your classes? Will the other developers do the same? Will the routine throw an error, or handle it itself? If handled, how will I know there was an error?

I know for a fact that if you don't lay out some very specific coding guidelines and design, four developers are going to design the same class four different ways, even when pairing. Given that fact, how can you possible write meaningful and consistent tests without doing a basic architecture/design first.

Second, writing tests is time consuming. Maintaining tests can be even worse. On this same project, test maintenance at times took more time than making a simple change. Why? When the change is made, many times a refactoring occurs (in our case it was almost a given since there was little thought placed on a unified design -- some day I will write on why that occurred as part of a human dynamics of development topic). Suddenly, the test needs to be re-written because the test now fails as a result of the refactoring. A simple business rule change has now turned into a design and test change. A task that might have taken an hour now takes two days. Sorry, as a business owner, it's a bitter pill to swallow.

Another mistake occurs when the developer takes on the attitude that when the automated tests pass, the testing is complete. Let's face it, as developers, testing sits right up there with documenting code. No one wants to do it, but it HAS to be done. With TDD, it's an easy trap to fall into. I even heard “My tests run, let the customer catch anything else in User Acceptance.” Wrong! The customer's are why we as developers have jobs. We need to do due diligence in functional testing, integration testing as well as usability testing. Automated testing is NOT going to do that for us. To think your automated tests are going to catch all the errors is dangerous thinking. No one has every promoted TDD to accomplish this, but I can tell you from experience, the possibility that this mindset can exist is there.

As I mentioned before, I am all for TDD and automated testing. However, I also like to be thorough. I also only like to write valid tests. If I was to sit there and ponder every single possible scenario, at my bill rate the client is going to be looking elsewhere thinking I am nor getting enough done. Consultants beware! But seriously, even if I could take the time to come up with test which can adequately test the possible scenarios, how much have I gained (in the short term -- long term is a whole other story which TDD clearly wins)? Testing scripts which repeatedly test the application, written by the users and repeated each time in user acceptance is a far more effective testing methodology (OK, devil's advocate time -- can you really get them to test it completely every time? The tester also suffers from laziness or lack of attention in repetitive tasks..) So writing tests is going to also be an iterative process which never ends. When a bug shows up, we need to refactor our testing to cover that scenario in the future. Now I am maintaining two projects which is even more time consuming.

The next fallacy in TDD is that the sheer number of tests (metrics) means you have good testing. In the environment I was working in, their reviews were actually based in part on the number of tests they wrote. Never mind that the majority of the test written were actually an effective test, but the sheer count was taken to be effective testing. Quality in testing should be your number one priority. If you can only come up with one test which effectively tests an object, then so be it. Adding five more test which do nothing other than add time during a refactoring is little help to the cause of good software.

Right now, automated testing really focuses on the Data Access Layer (DAL) and Business Objects Layer (BOL). When I discuss shunting next, you'll see it actually comes down to the BOL in many cases. What about the UI? The tools, especially for ASP.Net in the open source community are severely lacking in automated testing. How will you know if the javascript works both on Netscape and IE without running it yourself? It's the UI the user sees, which is why the UI has to be thoroughly tested in both how you expect the user to use it, and how they might use it. Users always come up with useful scenarios to break our applications. Think of it as a fun challenge and you'll be far less frustrated.

To test out our BOL, we shunted the data using XML or pre-defined data tables. It actually works great, but it's a limited test. What happens when the database schema changes? If you've shunted the data, you'll never know the impact unless you do your due diligence and fully integrate test, or the user finds it in user acceptance testing (which is not where you want to catch these things). If you do shunt your data, that's great and fine. Just make sure you test against the schema the application is going to be deployed against as well. See my blog about getting a random record using NewId() if you want to generate some good database based tests.

OK, it probably sounds like I am really bummed about automated testing after my recent experience with it. That belief is the farthest from the truth. In fact, I am going to introduce it on my current project because I feel it can certainly add a key dynamic to a complete testing process. But as Test Driven Development gains acceptance, I felt it was time someone at least mentioned the things to consider so it can be a more effective tool in your development cycle. Plan ahead and determine how you can avoid these pitfalls and hopefully your investment in time will generate more dividends from Test Driven Development.

My trek into automated builds

Tue, 23 Nov 2004 21:47:25 GMT

On my last project, as part of the agile process, we utilized nAnt with Draco.Net to create automated builds. I didn't implement that part of the project, but I certainly did see the value in automating the build. So, while I set up my environment for my topic of Component Based Development, I am going to write my learning's on generating an automated build. If you've used these tools, feel free to hop in and add some help.

That's one downside of open source projects -- the documentation can either be lacking or just as distributed. So hopefully by blogging about it, I can save someone some frustration.

So I am going to start by looking at the tools I am planning on using:

nAnt Home Page -- Get nAnt here. nAnt is the tool you'll use to configure your build

Draco.Net -- How to generate a build when your source control changes (or you trigger it)

Some other interesting links I saw:

For nAnt help: NAntUsage wiki -- Some help on how to use nAnt

For Draco.Net help: Draco.Net wiki -- Some help on how to use Draco.net

Tomorrow I am going to start implementing nAnt on a fairly complex project, so I will post my findings as I go along!

using log4net database storage -- review and database configuration correction

Sun, 21 Nov 2004 16:05:01 GMT

If you are looking to add logging to your application, whether for error logging or debugging or tracing, one decent option is the open source log4net. I give it a “decent” only in that there seems to be some bugs, and I am still not totally sold on the open source concept for a variety of reasons. But given that, some good thought has been placed into log4net, so that you have a good variety of options on where and in what format your logging information will be output. Note that I looked at v2, since it's the one which allows you to output to the database.

I am a huge proponent of logging error information to a database because you can check on errors real-time, as well as give yourself some powerful searching mechanisms. The client I was working for was logging to a file using an older version of log4net, so I decided to check out the log4net database functionality. Here's where you can find all the information you may want to know, including how to download log4net: http://logging.apache.org/log4net/

What I found was mixed. On the upside, you can (to a degree) use log4net with an existing database error log to a certain degree (I say to a certain degree because without going in an changing the source -- which is a plus for open source). A lot of thought has been placed into the design with regards to flexibility and performance.

On the downside, the code seemed buggy and the documentation is pretty bad. In order to get v2 database logging to work, I had to resort to stepping into the code to determine what the correct configuration settings would be. So as a bonus today, I will save the reader any heartache and post my file, along with a description of what the reader will need to change to use it!

First, I created a database (called test) in SQL Server 2000, and created a table called Log. Here's the fields, and I will leave the size out so you can make your own decisions about that, but given the amount of detail in the Message parameter of an error message, you might want to make some big varchars in there.

Column	Type
ErrorId	Identity (int)
Date	datetime
Thread	varchar
Level	int
Logger	varchar
Message	varchar
Exception	varchar

Create the table, then configure the log4net configuration file. Here's what mine looked like with the table structure above:

<?xml version="1.0" encoding="utf-8" ?>

<log4net debug="false">

<appender name="ADONetAppender" type="log4net.Appender.ADONetAppender">

<param name="BufferSize" value="1" />

<param name="ConnectionType" value="System.Data.SqlClient.SqlConnection, System.Data, Version=1.0.5000.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" />

<param name="ConnectionString" value="server=localhost;uid=test;pwd=test;database=test" />

<param name="CommandText" value="INSERT INTO Log ([Date],[Thread],[Level],[Logger],[Message],[Exception]) VALUES (@log_date, @thread, @log_level, @logger, @message, @exception)" />

<param name="Parameter">

<param name="ParameterName"&#0;value="@log_date" />

<param name="DbType" value="DateTime" />

<param name="Layout" type="log4net.Layout.RawTimeStampLayout" />

</param>

<param name="Parameter">

<param name="ParameterName"&#0;value="@thread" />

<param name="DbType" value="String" />

<param name="Size" value="255" />

<param name="Layout" type="log4net.Layout.PatternLayout">

<param name="ConversionPattern" value="%t" />

</param>

</param>

<param name="Parameter">

<param name="ParameterName"&#0;value="@log_level" />

<param name="DbType" value="String" />

<param name="Size" value="50" />

<param name="Layout" type="log4net.Layout.PatternLayout">

<param name="ConversionPattern" value="%p" />

</param>

</param>

<param name="Parameter">

<param name="ParameterName"&#0;value="@logger" />

<param name="DbType" value="String" />

<param name="Size" value="255" />

<param name="Layout" type="log4net.Layout.PatternLayout">

<param name="ConversionPattern" value="%c" />

</param>

</param>

<param name="Parameter">

<param name="ParameterName"&#0;value="@message" />

<param name="DbType" value="String" />

<param name="Size" value="4000" />

<param name="Layout" type="log4net.Layout.PatternLayout">

<param name="ConversionPattern" value="%m" />

</param>

</param>

<param name="Parameter">

<param name="ParameterName"&#0;value="@exception" />

<param name="DbType" value="String" />

<param name="Size" value="2000" />

<param name="Layout" type="log4net.Layout.ExceptionLayout" />

</param>

</appender>

<root>

<level value="DEBUG" />

<appender-ref ref="ADONetAppender" /

</root>

</log4net>

config.log4net (2.32 KB)

Of course, first thing you'll want to do is change the ConnectionString value to your situation. Now, some weird things I found. It doesn't seem to use the stored procedure it says it does. I stepped through the source, and it looks like it just tries to execute a SQL statement, which can be found in the CommandText parameter in the configuration file. So really, you could likely strip out all the parameters listed above. I have to confess it has been some months since I looked at log4net, so there might be a reason I left them in, such as a different part of the code that uses them and without it, it fails. So, take a few minutes and strip them out, and see what you get. But the saving you get from my slogging through the code should more than justify looking at this configuration file.

My final review is this: If you're creating a production app, here's your two options: roll your own solution or use log4net. If you plan on using log4net, download the source, learn it, and be prepared to spend some time (possibly considerable) debugging it. As a consultant, unless you need to ability to switch logging types (e.g. database to file to application log) dynamically, I would recommend rolling your own logging system, and write it such you can use it in multiple applications. Use log4net to get some ideas on the best way to accomplish it. Why? I think it tries to be too much to everyone, and it's not quite yet complete, and the documentation is lacking. In the end, KISS wins (keep it simple, stupid).

Making a page expire

Fri, 19 Nov 2004 14:40:51 GMT

We had a situation where the page wasn't expiring, and we were getting faulty results. So today's tip is a quick and dirty -- make the page expire!

private void EnsurePageExpires()

{

Response.Expires = -1;

Response.ExpiresAbsolute = DateTime.Now;

Response.CacheControl = "no-cache";

}

UI Abstraction -- Component Based Development Part #1 -- Description and Requirements

Thu, 18 Nov 2004 05:14:36 GMT

A very common task in application development is reporting. There are many tool packages out there which do a great job, such as Crystal Reports, Active Reports and the new kid on the block, SQL Server reporting tools. However, a lot of times these are overkill, or too expensive a solution.

Using ASP.Net, generating a UI for the results using a DataGrid or DataRepeater is very easy and can look professional in minutes. However, users typically aren't happy with just pulling out all the data. They want to be able to filter the data and quickly narrow down the data they need to see.

The solution is to create a data filter. A data filter provides a UI for selecting one or more criteria and limiting the results displayed to the items selected in the filter. Sometimes, the filter takes far longer to create for a deeloper than the actual report, and from my experience not one of the 'cool' functionality to add.

Case in point: A portal-based web site I helped develop for a large bank was about 90% reporting. By implementing base pages and styles, common grid functionality and libraries, I was able to get the turnaround on a report from 2 weeks to a day or so. As I analyzed the process, I noticed the report display only took a couple of hours, but the ensuing filter could take a day or more between layout, creating the filter items and modifying the query to handle the filter.

Subsequently, I developed the FilterWizard, which is a User Control which handles compiling the filter criteria, retrieving the data and making the data available to other controls, exporting to Excel, or anything which consumes data. The beauty of this control is that filters for individual fields can be added or removed with one line of code. The layout of the filter can also be altered by changing single values.

The requirements were fairly simple: Strong encapsulation of internal logic to a few simple methods (Primarly a single point of entry for formatting the individual filters, and a single point of entry for retrieving the values to filter on when the user pushes a [Filter] button). When the filter is triggered, the FilterWizard should notify the data consumer that data has been retrieved and is available for rendering.

When formatting the individual filters, the developer should be able to change the format of a filter simply by changing an enum value which represent the available filter types. Examples of filter types might be a single-select combo box, a multi-select listbox, a date range, a single value or a range of values. In the end, I wanted it as extensible as possible so if a new filter requirement came up, I could add additional filter types as quickly and easily as possible.

Finally, the FilterWizard should also be able to clear itself and reset the individual filters as well as display a summary of the filter values should the user choose to print the page.

There are actually two versions of this control. The first version used Dynamic SQL to create the filtered data. It was written in VB.Net. While Dynamic SQL provides some flexibility not easily duplicated using parameters, it's also more susceptible to SQL Injection. The second version uses C#, and used parameterized queries. I plan on discussing both because each has it's strengths and will reach a wider audience of developers by providing source in both VB.Net and C#.

What did I come up with? A great and easy to use control which provides all that functionality. And this is the start of my series on the FilterWizard which I will write more about, and finally provide all the source for in upcoming writings!

Now there's an idea for another topic (and a brief aside): C# vs. VB.net. I am a long time VB user and fanatic, but I have to confess C# is where it's at. I will certainly discuss this at length in the future, as there are definite advantages to using C# (which may go away in VS 2005) which I think are largely overlooked in other discussions on the subject. For now, let's suffice it to say if you have a choice, don't fear C# and jump in it head first. If not, use it when you can just so you are familiar with the syntax.

Debugging in .Net

Wed, 17 Nov 2004 15:29:26 GMT

I am actually amazed that this should be considered a tip, but since .Net came out, I have been at 3+ client sites working with other developers, and in every case, they didn't know how to set the debugger to break exactly where the error occurs. So, just to get back in the swing of things, I decided to post a quick tip on effectively using the .Net debugger.

So let's say you do your due diligence, and you have robust error handling in your application (I have actually heard the argument that's why you DON'T put error handling in, so you know exactly where the error occurs...but then again, so does your customer!). An error pops up, and your error trapping doesn't provide you with sufficient information (another difficult thing to do, considering the error object actually gives you the line number). The solution? Set the debugger to stop exactly on the line the error occurs.

To do it, open the Dubug menu, and select the Exceptions menu item as shown below.

You should then see the following dialog. Select Common Language Runtime Exceptions, and select the When the Exception Is Thrown/Break into the Debugger option, as shown below.

That's it! One thing you may find is only turning it on when you reach the page you want to debug, or you may be hitting a lot more than you want. Typically, in ASP.Net, I will set a break in the Page_Load, and turn it on, and reproduce the error.

Another interesting thing about the power of this utility is the ability to select individual exception types to break on, as shown below. Happy debugging!

It's official..

Thu, 11 Nov 2004 05:13:29 GMT

Today I signed my new contract to start a new project in a week. It's actually not a new project, but I was contacted by a former client and asked to return to help out with both new development as well as things I had previously worked on. To me, getting asked to come back means I must have done something right.

I was actually torn a bit on going back to the project. The offer was extremely generous, but there's the excitement of starting something totally new. The one thing about having a diverse set of clients is that you get exposed to something new each time. Even in cases where the challenges aren't great, the other developers aren't motivated or the project is mundane, I still manage to take a great deal of experience from them. Some good, some bad, but I do learn from them all.

Once I get the Component Based Development series done, I might just have to write about some of my mis-adventures of Independent Consulting. I was discussing this a bit as I signed the new contract. Everything from another contractor getting reprimanded for putting another employee's stuffed animals into compromising positions. At another location, the dba would frequently only speak Klingon. Yet another guy tried to extort the company whose domain name expire -- only to find out when he re-registered the name, he forgot to put it in his own name!

Genius... real genius out there. There's something to say for a guy like me who tries to act professional, shows up every day and plays well with others!

How to set style properties using javascript (and ASP.Net)

Thu, 11 Nov 2004 05:05:03 GMT

I ran across a situation recently where I needed to dynamically hide or show items based on whether or not a checkbox was checked. Simple enough if you know what items need to be hidden or not, but an easier and cleaner way was to set the appropriate CSSClass for the controls, then actually manipulate the style to do the work.

So how to change the properties of a style dynamically? Here's a snippet from a CodeBehind function, which was rendered in the Page_PreRender. The javascript was built in a StringWriter (sw), then rendered out onto the page.

        sw.WriteLine(@"if (document.all.chkMatch.checked)
");

        sw.WriteLine(@"document.styleSheets['Identical'].addRule
('.Identical', 'display:" + myStr + "block" + myStr
+ "'); ");

        sw.WriteLine(@"else");

        sw.WriteLine(@"document.styleSheets['Identical'].addRule
('.Identical', 'display:" + myStr + "none" + myStr + "');");

Here's the explanation. chkMatch is a server control checkbox (this is old code. it would have been better to use chkMatch's ClientId property when building this). When chkMatch is checked, the CSS class 'Identical' block attribute is set to 'block mode'. When unchecked, the style class is set to 'none', which has the effect of hiding any objects with the CSSClass property set to 'Identical'.

On a related topic, let's look at rendering scipt in include files vs. ASPX pages vs. CodeBehind. First, let's eliminate ASPX pages, since that means the code may be repeated, and we lose reuse. I suppose there's little difference between an include file and the code behind, because you can place common functions in both. However, from an encapsulation and organizational standpoint, I like CodeBehind because then I only add the exact scripts I need, instead of using include files which might contain a lot of extraneous functions. This is especially the case when I create User controls (which I do a lot of in my upcoming series on Component Based Development).

Feel free to write if you need further explanation. It's a powerful UI ability to be able to manipulate style properties dynamically from client side code!

What's Next?

Wed, 10 Nov 2004 04:58:13 GMT

I was thinking today that the daily tips are nice, there really isn't much I can't write about that hasn't been written about in terms of tips. So what can I write about that is not something I plan to make commercially available at some point, but can enhance the .Net community?

Today, I remembered an ASP.Net component I wrote which makes adding a complex data filter to a report as quick as a few lines of code. It's fully extendable and it demonstrates what UI abstraction can really do. I also have it already available in VB.Net and C#, and an example of building dynamic SQL as well as integration with stored procedures. It's in use for two of my large clients, and they swear by how much time it saves them, so hopefully it can save someone out there in Blog-land a bit of time too.

I'll still include my daily tips, but I think this will be a great beginning to contributing back to the ASP.Net development community which I have benefitted much from. So, stay tuned while I get the components into a nice same project using the Northwind database.

-- Daryl

WinCV -- Great .Net search tool

Wed, 10 Nov 2004 04:47:53 GMT

When you install the .Net framework, you also get a ton of utilities with it. For a complete listing, follow this link:

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cptools/html/cpconNETFrameworkTools.asp

One of these utilities is insanely useful if you want to find something fast, and you don't feel like going through the overhead and all the excess listings of the MSDN. This miracle utility is the Windows Class Viewer, also known as WinCV.exe.

To run it, use the .Net DOS prompt, and type in WinCV. You'll be able to enter a serach string (or partial string), and it will list the namespace it was found in, as well as the definitions of the accessible methods.

Now, the neat thing which isn't really mentioned is that you can include 3rd party searches by placing an entry in the WinCV config file. For example, I tested this by using the Infragistics libraries. Once I placed them in the config file, I was able to search them like any other Microsoft assembly. One caveat though -- it only works for assemblies registered in the GAC. I won't tell you exactly how to edit the config file, because if you can't look at it and figure it out, you probably shouldn't be editing that file.

Another Great tool

Tue, 09 Nov 2004 05:34:42 GMT

As a consultant, I need to be able to port a bag of tricks from one project to the next. Accessing MS Repository isn't always the easiest, although I have used it in the past for internal projects.

I ran across CodeLib for .Net by Fish, and it's a great tool, with searching, the ability to append files, notes, code (which it formats) as well as web pages (which I have yet to figure out how to work with).

Best of all, it's Freeware. So give it a try, you'll like it. Heck, once you get a library put together, maybe we can swap! ;)

Setting a control to ReadOnly using javascript

Mon, 08 Nov 2004 04:47:19 GMT

Have you ever wanted to make a server control appear normal, but be read only? If you simply set it to disabled, it's also greyed out, which can be a real pain display wise. So here's a couple of functions which will apply client-side javascript to the TextBox and DropDownList controls to prevent the user from being able to change the entries. Feel free to extend them to other controls (and forward them on! :))

    public static void SetControlReadOnly(DropDownList
ddlTemp)

        ddlTemp.Attributes.Add("onFocus","window.focus()");

        ddlTemp.Attributes.Add("ondblclick","window.focus()");

        ddlTemp.Attributes.Add("onClick","window.focus()");

    public static void SetControlReadOnly(TextBox
txtTemp)

        txtTemp.Attributes.Add("onFocus","window.focus()");

        txtTemp.Attributes.Add("ondblclick","window.focus()");

        txtTemp.Attributes.Add("onClick","window.focus()");

Changing the EncType of an ASP.Net form

Mon, 08 Nov 2004 04:40:15 GMT

On the project I am currently working on, the entire department uses the same Portal for hosting the different applications. That's great in that it promotes reusability, a common look and feel, quicker development and a central place for users to get all related information. I could go on and on, but I won't because there's one downside: flexibility.

We had a request from a user to allow uploading some files. Simple enough task, except our web pages all inherit from the same base web page, and there's no flexibility allowed in what we can do with that page. So, I had a dilemma. I had to give the user's the ability to upload files, but I couldn't change the base page that I HAD to use.

Simple enough, I would do a search for the form tag, and change the EncType dynamically! And here's how I did it...

Once again, I passed in the Page reference, because this sits in a common library. If you don't want to do that, just use the current Page reference. The other thing you might want to do is change the “form1“ reference as a parameter to make it more flexibility. At the time I wrote this, I knew it would never change, so I just left it..

    public static void ChangePortalEncType(Page
page)

        HtmlForm form1;

        if (page.FindControl("form1")
!= null)

            form1 = (HtmlForm) page.FindControl("form1");

            if (form1.Attributes["enctype"]
!= null)

                if (form1.Attributes["enctype"]
!= "multipart/form-data")

                    form1.Attributes["enctype"]
= "multipart/form-data";

            else

                form1.Attributes.Add("enctype","multipart/form-data");

Star Wars Trailer

Mon, 08 Nov 2004 00:48:09 GMT

Went to see the Incredibles today, and I am torn becuase while the movie was great, the new Star Wars preview really piqued my interest to see that one! Will next May never get here? :)

My son was only a little less excited about the preview. At 4, I hope it's not too scary for him, but all the other Star Wars weren't too bad, but he doesn't like sitting through the whole thing. I can't even begin to tell you how many times I have sat through the Factory scene in Attack of the Clones.

So, for a double bonus, go see the Incredibles, but make sure you get there early. And starting tomorrow, you can download the trailer!

Updated My Resume

Sat, 06 Nov 2004 17:32:25 GMT

Since I was looking for a new project last week, I went ahead and updated my resume. Turns out I didn't need to, as I had a new project before I started looking, but hadn't checked one of my email accounts before I sent word out to clients and recruiters I was finishing up a project. The resume needed to be updated, since it had been almost 2 years since I had to actively look for a project.

So here's a link to my resume if you want to see what I've been up to for the last 8+ years as an Independent Consultant.

Resume of Daryl Smith

Now I just need to find time to put some active content on my company web site. Time, time, time... never enough of it, especially if you have a life AND a family...

Creating a printable listing of fields in a table

Sat, 06 Nov 2004 16:45:22 GMT

On a rare occasion, I come across a circumstance where I can't create a SQL Server 2000 diagram, or the table is so huge and denormalized it doesn't really print from the diagram tool (which I love, BTW).

So, I ended up writing this little script which allows me to create a report which is easily printable. Yes, I am definitely a guy, as I am visually focused. :)

DECLARE @TableName VARCHAR(50)

SET @TableName = 'Authors'

select
'Table_Name'   = Left(sysobjects.name,25),
'Column_name'   = Left(syscolumns.name,25),
'Type'     = Left(type_name(xusertype),10),
'Length'    = convert(int, length),
'Nullable'    = case when isnullable = 0 then 'No' else 'Yes' end
from syscolumns, sysobjects where sysobjects.name = @TableName
and sysobjects.id = syscolumns.id
order by colid

Now, I imagine by now anyone reading these tips are saying “OK, nothing Earth shattering here..”. Give it time. Right now I am working on 2 projects, and it's hard to justify a lot of blogging time when I could be billing $XX per hour as many hours as I can stay awake and sane. At some point, I am going to write a series of articles on “Control Oriented Development”, and possibly give the keys to the city for a Questionaire engine I created which is basically limitless in how it presents questionaires to users. If you can think of a question, it can ask it... But that's down the road, so stick around!

Adding client-side script to the individual items in a RadioButtonList

Sat, 06 Nov 2004 05:31:28 GMT

I was faced with a challenge a while back where I needed to trigger a javascript function when an individual item was clicked in a RadioButtonList. Unfortunately, the standard Control.Attributes.Add functionality doesn't work here, because you can't directly access the rendered controls easily with the RadioButtonList. In this case, I wanted an image which indicated a required value to disappear anytime one of the options was clicked.

After a lot of playing around, I came up with this generic function which will append some script to each item in a RadioButtonList. You can further modify this to apply individual scripts to each item in the RadioButtonList.

        /// <summary>

        ///
Function to append client script to the onclick event of individual radiobuttonlist
buttons

        /// </summary>

        ///
<param name="rbl">RadioButtonList to apply script to</param>

        ///
<param name="page">The Page the script is going to be appended to</param>

        ///
<param name="script">The script to append</param>

        public static void SetRadioButtonListItemScript(RadioButtonList
rbl, Page page, string script)

            for (int idx
= 0; idx < rbl.Items.Count; idx++)

                RegisterClientObjectFunction(page, rbl, idx, script);

        ///
<summary>

///

        ///
</summary>

        /// <param name="page">The
Page the script is going to be appended to</param>

        ///
<param name="rbl">RadioButtonList to apply script to</param>

        ///
<param name="idx">the index of the radio button</param>

        ///
<param name="script">The script to append</param>

        static private void RegisterClientObjectFunction(Page
page, RadioButtonList rbl, int idx, string script)

            StringBuilder sw = new StringBuilder();

            if (!page.IsStartupScriptRegistered(rbl.ClientID
+ "_" + idx.ToString() + "script"))

                sw.Append(@"<SCRIPT>");

                sw.Append(@"document.all." +
rbl.ClientID + "_" + idx.ToString() + ".onclick=function()
{" + script + "return true;}");

                sw.Append(@"</SCRIPT>");

                page.RegisterStartupScript(rbl.ClientID + "_" +
idx.ToString() + "script",sw.ToString());

The key here is that each item in the list ends up with the ClientID of the RadioButtonList, then an underscore (_), and finally the index of the item. Once you have that, you have the keys to the city, as they say. In the example above, you are applying the same script to all items.

This function came out of a common library of mine. If your just going to place it on the page itself, you don't need the page parameter. You can just use the Page object itself. However, go ahead and throw it into a common library, because once you use it once, it's a pretty good bet you'll need it somewhere else in the future.

It's been a while...

Fri, 05 Nov 2004 05:17:14 GMT

It's been over a week, and no posts. Did I suddenly get lazy? Nope. Let's see. I went on a cruise, then came back and needed to land a new contract. If anyone says the job market is bad, better update your skills or your resume. I actually landed a new contract before I started looking which was quite a relief.

The downside of all of it was that I was told I needed to look for a new project the day before I left on vacation. Granted, it was like a 2 month notice, and should have been stress free since I was given ample time and a lot of freedom about it, but still when you know it's going to end, you worry about it. Secondly, I am not the type that likes to wait, but there was no point in looking until I could act on it. So, I enjoyed the time off as best I could. Fortunately, an old client of mine had called while I was away, and asked if I wanted to help out with a new project. The pay was very good, and the project sounded nice.

Now, that's not the point of this writing. Before I knew about this offer, I started looking as I had internet access. Being an independent contractor for years, I called in all my cards, afraid the election might make everyone nervous. Lo and behold, and much to the opposite of what the media was saying about the economy, the interest came in. If I received less than 8 serious calls per day this week, I would be surprised.

OK, serious is a slight exaggeration. Why? It's hard to keep a straight face when a recruiter calls, requests a VERY senior developer position, and then says the pay is $35 / hour. One recruiter even called two days in a row, becuase she ran when I quoted my standard rate the first time. The second day she called back, she couldn't remember why she didn't list me as a possible candidate, until I pointed out there was a very large discrepancy in what I consider a Sr. Developer rate and what she was offering.

All that behind me, there were still some promising leads. So I am not buying this whole “tech death” market. If you have skills and experience, and can market yourself, then there are good contracts still available.

Neat tool for blogging / web posting

Sat, 23 Oct 2004 16:31:16 GMT

Ran across this nifty little tool, so I decided to create a whole new feed dedicated to some neat tools I have come across in my travels. So here's the first one.

This tool is an addin which takes source code from the Visual Studio IDE, and formats it in HTML so you can post it on the web, in a blog, etc. It's easy to access and use, just a simple right-mouse click. And now the moment of truth, what it looks like:

 public static string ReadConfigurationValue(string p_strConfigString)

try

                string strValue
= "";

                System.Configuration.AppSettingsReader l_configurationAppSettings = new System.Configuration.AppSettingsReader();

                l_configurationAppSettings = new System.Configuration.AppSettingsReader();

                strValue = (string)(l_configurationAppSettings.GetValue(p_strConfigString,Type.GetType("System.String")));

                return strValue;

            catch (Exception
ex)

                ErrorHandler.LogError(ex);

                return "";

So far, it looks great. I will need to get used to a couple of little quirks, but all in all, I am impressed!

Where to get this great tool?

http://www.jtleigh.com/people/colin/blog/archives/2004/10/copysourceashtm_1.html

Enjoy!

Not so Bummed Anymore

Sat, 23 Oct 2004 03:37:20 GMT

Not a bad day. Finished my MCSD .Net (C#) finally (after putting off the final test for almost a year out of sheer busy).. and figured out what the problem with the RSS feed was. Good ol' URLScan was blocking some key functionality. A quick trip to the log file, and viola, we're good as new! So, FINALLY I think we have this thing configured! So, when I get back from vacation, let the real blogging begin!

Bummer

Fri, 22 Oct 2004 05:41:03 GMT

I was finally getting around to playing with dasBlog a bit, and noticed the RSS isn't working correctly (rather, the web service isn't). So, I *might* get a chance to fix it before I go on vacation, but it not, C'est le vie for a week. I suspect it has to do with security on the server, but we'll see....

Grabbing a random record using T-SQL/SQL Server 2000

Thu, 21 Oct 2004 05:58:16 GMT

In my Design section today, I ranted a bit about automated testing and a trend I have noticed to avoid directly accessing a database for that testing. It didn't start out to be a rant, but rather a tip about grabbing a random SQL record.

Using an ORDER BY NewID() clause, you can either randomly order your data, or grab a random single row. I use the single row method to grab data for testing so I am not always testing the same value, or occassionally the random order when I am searching for a particular set of data using a cursor for really complicated testing. Here's the usage:

Random order:

SELECT * FROM Authors ORDER BY NewID()

Single Random Record:

SELECT TOP 1 * FROM Authors ORDER BY NewID()

Automated Testing and Bugs

Thu, 21 Oct 2004 05:51:54 GMT

With the advent of test driven and test first development, writing meaningful tests can be a bear. There are a lot of methods, such as data shunting and hardcoding values, which avoid using the database for testing. While this can test the code, it doesn't test the database CRUD. I believe I once read that 80% of all applications are database applications, so testing the database portion is critical.

Personally, if you write tests which avoid directly testing your data schema and access methods, you're asking for trouble unless your Business Object tier is very robust. Even then, schema changes might be missed in testing if they don't actually interact with the database.

I am currently using nUnit for running the automated tests, and so far I absolutely love it. However, writing meaningful tests can sometimes take longer than writing the actual code, and as enhancements occur maintaining your tests can bog down the progress of the application. Changes inevitable, expecially in XP programming with their short development iterations.

Automated testing also invites buggy code if the developer is not careful. Here's some examples:

Some developers feel this takes place of unit and integration testing. This absolutely isn't true, as automated testing typically only checks individual functional testing (unless you have a very comprensive set of test cases developed -- suddenly these tests don't seem so agile).
Automated testing for the UI is limited at best. While nUnitAsp exists, it's not quite up to par to replace real-life beating-the-hell-out-of-the-UI testing.
There's absolutely no way to predict all of the ways a user if going to use your application unless you are a UI and Process Flow God/Goddess. Most programmers aren't, so you aren't going to be able to foresee all possible combinations of testing.

Bottom line is this. Use automated testing to test functionality against expected results, but this is only about 25% of the actual testing you need to do, regardless of whether the application is internal or external.

How a tip turned into a rant, I don't know.. So I guess I am putting this under Design, and making a second tip out of it.

Error Handling

Wed, 20 Oct 2004 04:09:24 GMT

As part of an ongoing discussion with a developer (let's call him JDOAGD) I am paired with, I had the opportunity to discuss the importance of Error Handling within an application. The two sides:

Minimalist -- only at the UI layer, and only then when the code is likely to fail
Solid -- Assume errors can happen anywhere, and handle them gracefully at ALL layers of a multiple application.

There's a school of thought that when an error condition occurs, throw an error or bubble it up to the highest layer and handle it. OK, that's a strategy, but what happens when the top layer doesn't catch the error? Crash. Fortunately, I was able to demonstrate this fact to the developer today who adamantly insisted on handling it at the UI only. He forgot to handle it, and BAM!, a crash ensued.

I wish I felt this was isolated, but I have had the privledge of working with several hundred developers over the past 10 years, and I would guess error handling is one of the most overlooked aspects of an architecture. Of those hundreds of developers, I would venture error trapping and handling was considered an afterthought by 90% of them. Some examples:

Degrades performance, so why do it? (how about a dead app really performs slow)
The applicaion is for internal customers, so they are more forgiving than if we were trying to deploy for general release
What's error handling and logging?

I recall a project which I was brought into a few years ago. The 4 developers had spent a month learning the business rules involved, and were chomping at the bit to get started. When I came in, they mentioned they were ready to code. So, I asked a few obvious (or so I thought) questions so I too would know how to code with them.

What's the error handling strategy?
What's the data access strategy?
What's the physical architecture?
What type of security model are we implementing?
...and many more.

Scary thing was, they didn't have an answer for any of them. The other scary thing was they were billed as “Expert Coders” and were billing at a significantly higher rate than myself. Had I less ethics, I would have asked for more $$ instead of pushing to resolve these issues. That whole project was “interesting” to say the least and someday I might write more about those experiences.

Back to today. So, since I am on their payroll, I listened to JDOAGD's reasons for not having error handling except on the UI layer. I watched him also forget to place any at the UI level he was so adament about it. I had the hook, and he finally saw the light. What was my point?

In a multiple developer environment, you can never assume the other develper using your code will trap the error (this is an encapsulation issue, which this same developer once vehemently added encapsulation was a bad thing. In a non-web environment, crashes kill the application. The browser is very forgiving!

Finally, internal or not, as developers we are serving customers. Without them, we'd have no jobs. It's important to ALWAYS give them the best possible user experience. Anything else is simply lazy and unprofessional.

Logging is a whole other issue, which I will save for a future session. For now, I'd love to hear other opinions and experiences in this area, so please, drop me a comment!

-- Daryl

DBA Must Haves IMHO First A Little About Myself I Have Been Working With Databases Since SQL Server 6 And A Lit

Tue, 19 Oct 2004 14:07:53 GMT

DBA Must Haves (IMHO)

First, a little about myself. I have been working with databases since SQL Server 6, and a little back when it was Sybase. Here are two procs I use so much, I have to link them here.

First, there's Narayana Vyas Kondreddi's sp_generete_inserts. It's a great utility/sproc for extracting data from existing tables. I have used it from everything from migrating data to making impromptu backups to text files, all the way to bailing out some hapless developers who run against production and wipe out data they should not be touching. Here's where you can get it:

http://vyaskn.tripod.com/code/generate_inserts.txt

Next, there's sp_findsp. Not the prettiest thing, but if I want to find out where a string (such as a table or proc) is used, I can run this baby and it will return to me a list where I can start looking. It's also very useful to me when I start a new project to do some “mining“ to see what's going on. Here's where this one can be found:

http://databasejournal.com/features/mssql/article.php/1458871

These two follow me everywhere I go!

Tip of the Day begins...

Tue, 19 Oct 2004 13:55:14 GMT

This section is going to be where I place as many tips and tricks as I come across them. I will try to attribute whomever I get the tip from where appropriate, but I apologize in advance if I forget. They say imitation is the highest form of flattery, so if I use it, consider yourself flattered! :)

Since I work multiple projects at a time, these tips and tricks will generally be posted as I discover them. However, I have a whole library of useful functions I can pull from, so hopefully I won't dry up any time soon.

Introduction!

Daryl — Tue, 19 Oct 2004 03:11:43 GMT

I have finally decided what to do with this domain. Originally, it was intended to host tips and tricks about using .Net that ihave acquired over the last couple of years using .Net. That hasn't changed, but as I enter the blogging world, it's going to get a bit easier to accomplish, I hope.

What took so long? Business, business, business... It's hard sometimes to justify doing something like this when there's a ton of billable work which can be done. I wanted to design the site, but it's hard to do when other people are willing to pay you to design their sites. Heck, my original site is still static HTML, and I didn't even design that one myself, since I had helped a web designer out, he decided to help me by making my site pretty. While I still like it, I want to move in some active content and play around with things on the site, especially when it comes to do with some of the projects I have been working on for the past couple of years since I became involved with .Net.

What do I plan on writing about? For starters, I want to share some tips and tricks I have picked up. Other topics will be rants and raves about everything from development methodologies I have been involved with (or thrust in, as the current case is). I am a gadget freak, so you might hear me review off-handed a few I like or dislike.

So if you are still here, enjoy the ride!

-- Daryl