Tips for C# Developers

Testing with Visual Studio 2010

2012-01-14T20:45:00.003+01:00

The last time I am discovering more and more the test features of Visual Studio 2010. In this blog item I discuss or mention some of these features.

It is possible to execute a code analysis after each developer build. You can enable (or disable) this in the properties of the project; see tab Code Analysis. There are several rules you can configure (globalization rules, basic correctness or of course you can customize these)
It is also possible to measure the quality of the code, with Code Metrics. Code metrics gives some overview in maintanability and complexibility. The code metrics can be used to give a progress overview in a refactor proces to the management, simply export this data to Excel. The index for maintability, complexibility, depth, code coupling and lines of code.
With the Test Impact Analysis feature Visual Studio shows you the tests which are affected on the code change. (use the Test Impace Window)
There are several tests; Code UI Test, Load Test and Web Performance test. You can also use profiling for your application. You can select CPU Samples, Instrucmentation and compare the results and find the method or class which is the most expensive.

Load Tests in Visual Studio

2012-01-06T20:48:00.004+01:00

With the help of Visual Studio you can setup a Load Test. A little part of the Load Test is a Web Performance Test (prev. Web Test). A requirement for executing the test again and again without having recording it again is that the ids of the web controls are the same, between postbacks AND IIS restarts. If this is NOT the test will fail, you can solve this by making the web control id constant or maybe you can create an Extraction Rule

Lektober

2011-10-03T11:11:00.008+02:00

Webwereld heeft de maand oktober uitgeroepen tot Lektober maand. Iedere werkdag komen lekken op websites aan de orde

Use Static Properties Instead of the Application Object to Store Application State

2011-09-27T15:17:00.008+02:00

You should store data in static members of the application class instead of in the Application object. This increases performance because you can access a static variable faster than you can access an item in the Application dictionary. The following is a simplified example.


private static string[] _states[];
private static object _lock = new object();

public static string[] States
{
  get {return _states;}
}
public static void PopulateStates()
{
  //ensure this is thread safe
  if(_states == null)
  {
    lock(_lock)
    {
        //populate the states…    }
  }
}
public void Application_OnStart(object sender, EventArgs e)
{
  PopulateStates();
}

Web Deployment Package

2011-07-28T08:40:00.002+02:00

I have never worried about deploying a website. But it takes more and more time, so I have looked today for Web Deployment Package. This is a feature of VS2010 (or is it already included in VS2008?) this looks as a nice feature. I will analyse this in more detail and write the conclusions on this blog. When someone has some tips, let me know;)

Vista folders views keeps changing

2011-01-02T11:21:00.001+01:00

An annoying thing in my Vista installation, was that the Folder views from Explorer keeps changing. Finally I have found a solution for it. Propaply this solution was long time ago developed, because Windows 7 is already released. But better late, then never;)

Configsource

2010-12-18T16:41:00.003+01:00

A collegua of me sent a while ago a link about ConfigSource. I think this is an easy way for dividing the web.config is some logical parts. So I am goiing to use this in my (private) projects. Unfortunately the external file must be in a relative physical path to the application because of security reasons.

Update:The attribute configSource works only for a complete section and NOT for a single ConfigurationElement.

ToOADate

2010-12-06T19:54:00.002+01:00

For a couple of my hobby web sites I use an Access database. When I upgrade these website to ASP.NET 4.0 Framework I have had also to update some calls to the database for the DateTime columns, I have to use the ToOADate() method.

Repeater: Custom ItemTemplate

2010-11-17T13:25:00.002+01:00

When you want to create a custom item template in a repeater you have to readthis article. In this article the css-class and the html depends of the content of the data collection. So you want a different ItemTemplate for another row.

Web.config customErrors element

2010-11-17T13:20:00.002+01:00

In de web.config of a (web) application it is possible te configure the customErrors element. Mostly for development I want to see the details of the errors so I can fix these quickly. But when the application runs for end-users I want to be informed about these errors and the users sees a friendly message "there is something wrong, this is registrerd".

ildasm.exe

2010-11-01T08:07:00.002+01:00

In the command prompt of Visual Studio it is possible to call the windows tool
ildasm.exe. With this tool the assembly manifest is readable and so the related assemblies can be retrieved.

Public token key

2010-10-18T12:27:00.001+02:00

With the 'sn.exe' tool of Visual Studio it is possible to retrieve the public token key. But watch for the casing!!

Use the command: sn.exe -Tp "FilePath to assembly"

Fiddler and localhost

2010-10-12T08:37:00.004+02:00

Working with Fiddler for seeing the details of the Http request of a website is usefull for optimizing the performance of a website. Check if there are unneeded requests or if there are many requests which triggers a 404.

A tip when working with localhost you must http://localhost.:1519/default.aspx instead of
http://localhost:1519/default.aspx. So add a point behind the hostname.

IEnumerable Empty

2010-10-12T07:34:00.003+02:00

When creating an IEnumerables, I mostly returned a null value when there are no values for the collection. But it is in some situations better to return an empty collection. This can be done with the Enumerable.Empty method.

Short cuts in Visual Studio 2010

2010-05-28T07:36:00.001+02:00

shortcuts of Visual Studio 2010

How to take ScreenShot in C#

2010-05-19T08:33:00.001+02:00

From this article I have copied the code below for taking a screenshot. I have not yet tested this code, because I do not reminder where I need this... when I do I will update this post:)

here is the code in C# for screenshot.

int screenWidth = Screen.GetBounds(new Point(0, 0)).Width;
int screenHeight = Screen.GetBounds(new Point(0, 0)).Height;
Bitmap bmpScreenShot = new Bitmap(screenWidth, screenHeight);
Graphics gfx = Graphics.FromImage((Image)bmpScreenShot);
gfx.CopyFromScreen(0, 0, 0, 0, new Size(screenWidth, screenHeight));
bmpScreenShot.Save("test.jpg", ImageFormat.Jpeg);

.NET Framework 4

2010-04-30T14:26:00.002+02:00

Since the beginning of this month is .NET Framework 4 released. When migrating to a newer version of the framework, there are always some issues. These issues are listed on the MSDN site. Hope it helps!

Update: Some changes from another view

Embedded Resources

2010-03-25T11:15:00.001+01:00

When you work with embedded resource, you can use the following code to get a list of all the embedded resources in de current assembly:


foreach (string s in this.GetType().Assembly.GetManifestResourceNames())
      System.Diagnostics.Debug.WriteLine(s);

More info on How to use assemlby embedded resources

Check your web.config

2010-03-12T08:37:00.001+01:00

Check your web.config on these common mistakes which occurs in the web.configs.

IIS 7 and IIS 7.5

2010-03-12T08:32:00.002+01:00

The IIS version for Windows Server 2008 (Vista) is IIS7 and the IIS version for Windows Server 2008 R2 (Windows 7) is IIS 7.5. read more information about specific details. At the moment it is not clear for me what the difference are for configuring a web application in IIS 7 and IIS7.5, specially for the web.config. When I know more about this, I will blog this....

Browser capabilities

2010-03-12T08:29:00.002+01:00

Test your browser capabilities on this site. When you use the Developer Toolbar for disabling Javascript or CSS support you can see the results on this page. Also useful for crossbrowsing web development.

Name Mangling

2010-03-08T09:17:00.002+01:00

Name Mangling is a definition which is used inside a programming language. For example: A compiler uses this, for unique identification for private fields by prefixing the private fields with the class name.

LINQ: ToLookup vs ToDictionary

2010-02-17T11:21:00.001+01:00

A nice article about LINQ: ToLookup vs ToDictionary

Taking Shapshots in ASP.NET

2010-02-08T07:48:00.002+01:00

On the blog of ENES TAYLAN I have found an article about Taking Shapshots in ASP.NET. It is a nice feature, but it must be provided as webservice, in the example on this page it can only be used a stand-alone.

Which exceptions are there in .NET?

2010-02-08T07:45:00.001+01:00

On the blog of Mikesdotnetting there is a article which summaries some exceptions from the .NET Framework. So these can be used.

Callbacks

2010-02-05T07:56:00.001+01:00

Some information about callbacks

How to get an indexed item of an IEnumerable object (Linq)

2010-02-01T07:51:00.002+01:00

How to get an indexed item of an IEnumerable object (Linq), this is a question which I often have had when I start using IEnumerable. But it is possible with the ElementAt() extension method!.

Adding a Reference Path to all your .NET projects

2010-01-27T15:49:00.000+01:00

Adding a Reference Path to all your .NET projects

Get the name of the method

2010-01-22T10:52:00.002+01:00

Sometimes it is easy to print the methodname of the current method. This can be typed manually, but with use of Reflection this can be retrieved with the following simple command:

System.Reflection.MethodBase.GetCurrentMethod().Name

Log Parser

2010-01-11T19:27:00.001+01:00

Log Parser is a usefull tool for reading and analysing IIS logfiles.
Download Log Parser

Reflector

2010-01-09T13:57:00.002+01:00

Reflector is a tool for disassembly a dll. So you can see the source code and you can analyse if the assembly works correctly.

Link dump

2010-01-09T12:38:00.003+01:00

Loading Message with Ajax
http://weblogs.asp.net/aghausman/archive/2009/07/20/show-loading-message-in-asp-net-ajax.aspx

Resolve urls with Javascript
http://weblogs.asp.net/joelvarty/archive/2009/07/17/resolveurl-in-javascript.aspx

Logging guidelines
http://www.bugfree.dk/blog/2009/07/22/basic-logging-guidelines/

Enterprise Library Logging

2010-01-09T12:36:00.001+01:00

For logging exception the Enterprise Library an usefull tool.

.NET Validators

2010-01-09T12:18:00.002+01:00

When using 'Validators' you must use the property "IsValid" and you must use the method "Validate".
For a CustomValidator you must implement the 'ServerValidate' event.
Also the property 'ClientValidationFunction' must be set to organize the Client side validatie.

source: validator
arguments.value: the control which must be validated
arguments.isvalid: true if the value is valid otherwise false.
- http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.customvalidator.aspx
- http://www.codeproject.com/KB/validation/MultiDependValidator.aspx

Do not use underscores in DNS computer names

2010-01-09T10:48:00.003+01:00

The support of Internet Explorer with underscore is not the same as for browsers like firefox and chrome.

Take the following address: http://pc02_test.domain.com/webapp

When you now want to store some information in the cookie, this goes wrong. So the advise is do not use underscores!

More information:

- http://social.msdn.microsoft.com/Forums/en-US/iewebdevelopment/thread/8e876e9e-b223-4f84-a5d1-1eda2c2bbdf4
- http://www.enhanceie.com/ie/bugs.asp (IE005)
- http://support.microsoft.com/kb/909264

Environmental overrides with Enterprise Library

2010-01-09T10:35:00.002+01:00

For the most application there are several environments available. Each environment has his own configuration (like connection string, files and so on).

With Enterprise Library you can create environments and override some properties of the web.config. See for more information: Environmental overrides.

Unit testing losse flarden

2009-12-29T19:33:00.003+01:00

Wanneer je start met unit testing, zijn er diverse handvaten die je kunt gebruiken om unit testing te gebruiken in je applicaties.
In de test logica mag je geen gebruik maken van
- IFs statements
- Switch of case statements

- Vervolgens moet de test code die je opstelt herhaalbaar uitgevoerd kunnen worden.
- Vermijd Multiple Asserts.
- Integration test en een unit test moet je scheiden
Alle testen in de solution runnen, wanneer een test failed dan is er een probleem. Dus -> betere test
-> integration test
-> er is geen configuratie maar je moet de test vertrouwen
Een verschil tussen een unit test en integration test is dat bij een integration test configuration noodzakelijk is. (gebruik de postfix unittest en integrationtest voor de desbetreffende testen)

Bij 'gewone' code geldt al gebruik GEEN magic numbers, en dit gaat ook op voor test code.

Syntax method names (bij testen
- method name
-state undertest
- expected behavior
-> dat leidt tot 'Add_LessThanZero_ThrowException'.

Helper methods
- '_make' -> create
- '_change' -> update
- '_assert_'

- Alleen public testen. DIt is een contract naar buiten toe. Private/protected is voor intern gebruik en meer verandelijk.
- Incremental work! (stapje voor stapje)
- [setup] attribut, dit is uitgevoerd voor ELKE test
- start een fail test, de test mag niet blijven 'falen' als de productie code is aangepast
- TDD -> vind de bugs sneller
- Simple code kan bugs bevatten
- Test names zijn lang maar dit is readabily (documentatie)
- Duplicated de logic in de test is een probleem, je test de logica niet. Het eindresultaat is niet gecontroleerd de bug wordt gewoon opnieuw gecreereerd in de Assert.AreEqual. Unittest mag geen logica bevatten, zelfs geen string.Format etc.
- Verander nooit een test. Als een test niet goed is (failuing test). Tegenstrijdige requirements vraag na welke requirement geldig is.
- Code coverage

SQL datetime headaches

2009-11-07T10:59:00.003+01:00

I'm always hassleing with datetimes in the SQL Server database to get the correct datetime format that i want. It seems that most of this stuff you can do with specifying a format when converting it:
Usefull page for that

But it did not realy have what i wanted from it.

So the final solution was the following
to get a format like this:
2008-11-13 17:29:00

I needed to do the following

SET generated = cast( getdate() - 8 as smalldatetime)

WCF service error contract name not found

2009-11-07T10:49:00.004+01:00

I had a stupid error a few weeks back which involved a WCF service, A end of the day configuration issue and some totaly unrelated error message. In short after googleing i came across the solution and i decided it was one to remember.

solution on the blog of Peter Morris:

The contract name xxxxxxx could not be found in the list of contracts implemented by the service

So what you need to do:
Check names of interfaces
Check namespaces
Check the service attributes ([AspNetCompatibilityRequirements(RequirementsMode=AspNetCompatibilityRequirementsMode.Allowed)])

What is Inversion of control and Dependency injection

2009-11-07T10:37:00.003+01:00

recently we started to use Unity for projects. Unity is a way to facilitate dependency injection into you code.

And we where using some of the terms often related to this topic and it was confusing me. I decided to get my facts straight.

Inversion Of Control

Inversion of control article that i have found usefull

http://martinfowler.com/bliki/InversionOfControl.html

This article states that inversion of control is a priciple.

a short statement that signifies the base principle:

"Don't call us, we will call you"

the principle comes down to the following:
A Control gets all his data and events from the outside and itself does not know anything about the context it is being used in. This results in lousely coupled Code/controls which in turn should make them more reusable.

Dependency Injection

Dependency injection is a way to achieve Inversion of control

http://martinfowler.com/articles/injection.html#ComponentsAndServices

http://www.codeproject.com/KB/aspnet/IOCDI.aspx

Conlusion

Inversion of control is a principle with the goal to help you create better, more reusable code

Dependency injection is a specific method of achieving inversion of control.(Unity is a method for dependency injection)

Path resolution through IUrlResolutionService

2009-11-07T10:18:00.006+01:00

When developing for a web application you often come accross the scenario where you need to generate a path to a different page and all you have is a app relative path. To resolve this path to a usable client path i have often used different methods to resolve a path.

When working on a project at work i saw a colleage use the following interface
IUrlResolutionService

I had never seen that one before and i looked it up
MSDN page

Quote from the page:
Defines a service implemented by objects to resolve relative URLs based on contextual information.
....

Remarks

This interface defines the service that is used to resolve URL paths. The IUrlResolutionService interface is used for resolving relative paths and paths that contain the ~ operator. Server controls that reference resources can define the paths to the resources through the ~ operator, which represents the root of the current application. A path containing the ~ operator will not work if passed to the browser. The server control must convert the path to an absolute or relative path before passing it to the browser.

Control implements this interface. A control that derives from Control could override this implementation to provide customized resolution of URLs.

This interface is implemented by the Control, among other classes, which means that Controls like Page, etc all have a method to resolve the path.
you can pass along controls or the page deeper into your code using this interface to resolve app relative paths for you. For example "~/foo/bar.aspx" would get resolved properly by the control to a path the client can use based on the current context of the control/page.

I myself are using this more often these days it seems a nice way to do it.

Steps until failure

2009-11-07T10:14:00.003+01:00

This is a piece of code i came accross that i thought that was interesting. I came accross this piece of code and i thought i should remember it for future reference

on Found on the website:
http://odetocode.com/Blogs/scott/default.aspx

void Process(){

Func<bool>[] steps = {
Step1,
Step2,
Step3,
Step4,
Step5
};

ExecuteStepsUntilFirstFailure(steps);

}

void ExecuteStepsUntilFirstFailure(IEnumerable<Func<bool>> steps)

{
    steps.All(step => step() == true);
}

The All operator is documented as stopping as soon as a result can be determined, so the above code is equivalent to the following:

void ExecuteStepsUntilFirstFailure(IEnumerable<Func<bool>> steps)
{
    foreach (var step in steps)
    {
        if (step() == false)
        {
            break;
        }
    }
}

Environment.NewLine

2009-10-29T08:25:00.001+01:00

When you create a string with must have multiple line use the option Environment.NewLine and not the escape characters.
see

Some Anti campaigns

2009-10-23T21:55:00.000+02:00

Most programmers use the 'if' and 'loop' statements very much. But when you use this too much, your code can be less readeable. So some blogs have campaigns to minimize the usage of these statements:
- Reduce FOR
- Reduce IF.

Convert VB.NET to C#

2009-10-23T21:49:00.001+02:00

Since my new job I have to work a little bit more with VB.NET. So here some tips for converting C# (.NET) and VB.NET and the other way around.

On this site some links can be found, for quick links for converting VB.NET to C# and vice versia.

Further there are some difference between those two languages. Some of these differences can be readen here.

Nested repeater programmatically

2009-10-23T21:47:00.000+02:00

On this site I have found some information for creating Nested repeaters programmatically.

Create PDF in ASP.NET

2009-10-23T21:44:00.000+02:00

Earlier I have created PDF file from a .NET (web) application with the help of XSL:FO. But my experience was not very good. So I have found a Tutorial for creating PDFs. With this tool you can create PDF files with OO technics, this sounds much better.

Tip: Linq to SQL

2009-10-13T08:05:00.001+02:00

When you are using Linq to SQL, you have to read (and use) these tips.
I mostly use Linq to Objects, but when I am going to use Linq to Sql is will read these tips again:)

Tool SourceCodeOutliner

2009-10-12T15:38:00.001+02:00

I have read something about the SourceCodeOutliner tool. This is a plugin for Visual Studio which organize your class file in a tree. So you can quickly navigate to a field or property.

I am not yet using it. But I think I will give it a try for a couple of weeks.

.NET Versions

2009-10-11T09:07:00.001+02:00

With System.Environment.Version the version of the Common Runtime Language is returned.

In the next switch statement an example of using the Version property:


switch(System.Environment.Version.ToString())
{
case "1.0.3705.000" :
{
Response.Write(" (.NET 1.0)");
break;
}
case "1.0.3705.209" :
{
Response.Write(" (.NET 1.0 SP1)");
break;
}
case "1.0.3705.288" :
{
Response.Write(" (.NET 1.0 SP2)");
break;
}
case "1.0.3705.6018" :
{
Response.Write(" (.NET 1.0 SP3)");
break;
}
case "1.1.4322.573" :
{
Response.Write(" (.NET 1.1)");
break;
}
case "1.1.4322.2032

Overview of .NET versions from the Framework.

Reading attribute with ConfigurationElementCollection

2009-10-09T13:36:00.004+02:00

I was programming a part of a configuration file like this

I will use the ConfigurationElementCollection.... so the elements are not very difficult. Create a class for the element with the properties name and url and use this in a class which derived from the ConfigurationElementCollection.

But getting the value of the title attribute on the element is more difficult. I have not yet found a nice way to do does. For now I am use a dirty hack.

Google Webelements

2009-10-07T19:36:00.002+02:00

With Google Webelements you can create a web element for your web site. On the page you can customize the web element and when you have entered all the settings you simply copy the html in your web site and your web element can be used on your web site.

Design conventions properties and methods

2009-10-07T19:25:00.003+02:00

On the blog of Wesley Bakker I have read the following article. Most of this stuff is really basic, but it is always usefull to repeat this. So conform your code to the design conventions for properties and methods, when you do not some other developers which use your code can make wrong assumptions.

XMLSerializer and invalid XML

2009-10-05T08:13:00.002+02:00

On the blog of Raj Kaimal I have read the following article about xml serialization.
The conclusion of this article is the existence of the System.Xml.XmlWellFormedWriter class which can be created with the XmlWriter.Create method.

New Ajax Toolkit

2009-10-01T07:46:00.004+02:00

In this article some new controls of the new ajax toolkit

Download the new release here:
http://ajaxcontroltoolkit.codeplex.com/Release/ProjectReleases.aspx?ReleaseId=33804

Try the live demos here:
http://www.asp.net/ajax/ajaxcontroltoolkit/samples/

Configure test projects in Visual Studio

2009-09-25T07:48:00.001+02:00

I have not done anything reals with test projects in Visual Studio but on Platinum Bay there are some options for configuring the test projects in Visual Studio.

.NET Framework 1.1. on Vista

2009-09-11T11:16:00.000+02:00

When you want to install and use the .NET Framework 1.1. on a PC where Vista is installed read the following article.

Reset auto number from a SQL table after delete

2009-09-11T11:10:00.003+02:00

When you have an auto number on a table and you deletes the rows in the table you have to reset the autonumber value.

DELETE FROM tblName
DBCC CHECKIDENT (tblName,RESEED, 0)

The first lines throws all the rows in tblName away and with the second row the auto number is reset

read here more information

Fill a dropdown with month names

2009-09-10T11:03:00.003+02:00

On Jeff Widmer's Blog there is an >article about filling a dropdown with the month names. It sounds very simple to me, but when you digging into the code you will see that for months there is not a nice solution as for the DayOfWeek:(.

VS2010: Multi monitor

2009-09-01T08:11:00.002+02:00

On the Blog of Scottgu he write about the support of mulit monitors in VS2010. This sounds very nice, I will try this when I have installed a version of VS2010...

Fun flow diagram

2009-08-28T08:04:00.002+02:00

I have found a very funny flow diagram on xkcs. In this diagram non-computer people gets some instructions what do to when they getting an error on the pc BEFORE calling 'computer experts'.

Convert usercontrol to control

2009-08-25T17:11:00.001+02:00

This article contains some instructions how to convert a UserControl to a Control.

.Root in Source Safe

2009-08-25T13:08:00.002+02:00

Frustating everytime I created a project the postfix ".root" is added. Finally I have found a site with the same problem (or an the MSDN website and a SOLUTION.


You are running into a feature referred to as 'Solution Root' added 
to VS2003 (and carried forward into VS2005).  You can disable this behavior 
via the following registry entry:

HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\8.0\SourceControl\DoNotCreateSolutionRootFolderInSourceControl

Builder versus Factory pattern

2009-08-25T12:52:00.001+02:00

Copied from some other website, unknown which one...

Difference Between Builder pattern and Factory pattern
The factory pattern defers the choice of what concrete type of object to make until run time. E.g. going to a restaurant to order the special of the day. The waiter is the interface to the factory that takes the abstractor generic message "Get me the special of the day!" and returns the concrete product (i.e. Hawaiian or Spicy pizza)
The builder pattern encapsulates the logic of how to put together a complex object so that the client just requests a configuration and the builder directs the logic of building it. E.g The main contractor (builder) in building a house knows, given a floor plan, how to execute the sequence of operations (i.e. by delegating to subcontractors) needed to build the complex object. If that logic was not encapsulated in a builder, then the buyers would have to organize the subcontracting themselves ("Dear, shouldn't we have asked for the foundation to be laid before the roofers showed up?")
The factory is concerned with what is made, the builder with how it is made. Design patterns points out that Abstract factory is similar to builder in that it too may construct complex objects. The primary difference is that the Builder pattern focuses on constructing a complex object step by step. Abstract factory's emphasis is on families of product objects (either simple or complex). Builder returns the product as the final step, but as far as the Abstract Factory is concerned, the product gets returned immediately.

_Blank variant

2009-08-25T08:37:00.002+02:00

On old school tip... when you do not want to use "target=_blank", you can the use following javascript.


<a onclick="window.open(this.href,'_blank');return false;" href="http://some_oother_site.com">Some Other Site</a>

TemplateSourceDirectory invisible

2009-08-25T08:32:00.002+02:00

TemplateSourceDirectory can be overridden in the following way:

new public virtual string TemplateSourceDirectory
{
  get
  {
    return Page.TemplateSourceDirectory;
  }
}

Now the property is invisible for other classes.

Set time-out-time

2009-08-25T07:47:00.002+02:00

On the blog of Sujith K Jagini there is a article with some information about
Time out exceptions. How can the 'time-out-time' be set in a WCF service, web service or for (SQL) database.

SQL injection prevention

2009-08-24T09:42:00.002+02:00

Last weekend the website of FOK was hacked. It is easy to prevent SQL injection, read the article below:
How to prevent your application from SQL Injection.

Not showing a login page

2009-08-20T13:16:00.000+02:00

When you uses .NET web application authentication the user is automatically redirected to the login screen. Here there is an example how you can prevent this, and now you can show the 'Access denied' page.

SEO: Viewstate on top

2009-08-20T13:13:00.000+02:00

The rules for better SEO on your website are not static. So it is better to set the Viewstate information at the bottom of your webpage. How you can do this can you read here.

Composited control

2009-08-20T13:10:00.000+02:00

Here you can read something about composited controls. (with validators)

In Place Editing

2009-08-20T13:09:00.000+02:00

With the control of AJAX.NET it is now (easy) possible to create a website where the user can update the content with a click on the content which must be updated.

On Misfit Geek there is a nice startup tutorial about Inplace editing.

Redirect Session Expiration

2009-08-20T13:04:00.001+02:00

On Schnieds Blog I have read an piece of code about Redirecting when the session is expirated.

I have not yet used this, but it seems nice to integrate this in a webapplication which uses form authentication.

more info

Serialization in ASP.NET (2)

2009-08-19T13:30:00.000+02:00

Starting with serialization....uhhh I always forget that... I have found a link with an easy example which can be used as startup code fragment.
Simple example for serializing and deserializing

Web Site or Web Application

2009-08-19T13:28:00.000+02:00

When you start building a web appication with Visual Studio you must decide which type you use:
- a web application project
- a web site project (introduced in VS2005)

Some links with information about this discussion
- ASP.NET Resources - Web Site vs Web Application Project (WAP)
- ASP.NET Web Site Layout
- asp.net Web Site versus Web Application Project
- ASP.NET Website vs Web Application project
- Understanding Page Inheritance in ASP.NET 2.0 - Rick Strahl's Web Log
- Web Site or Web Application - Blog
- Website versus Web Application - Durban, South Africa

But the conclusion of most of these sites is: decide it by yourself!

Convert Website to Webapplication

2009-08-19T13:27:00.000+02:00

When you want to convert a Website to a webapplication you can read
here some instructions for doiing this.

Parameters queries in Access

2009-08-19T13:25:00.001+02:00

When developing websites for 'fun', mostly I will use an Access Database. In SQL server you have stored procedures and you can give values to them with params. This is also possible in Access, but Stored Procedures are called Queries and a nice example can be found here.

Tabs in Jquery

2009-08-19T13:22:00.000+02:00

On Mikesdotnetting I have read the article about JQuery and Tabs.

I have sent a comment with the questing how to navigate directly to a specific tab? Example of navigate directly to a specific tab

Only IE7 in IE8

2009-08-19T07:53:00.001+02:00

Force IE7 compatibility mode in IE8 with a single line in the header of each webpage.


<meta http-equiv="X-UA-Compatible" content="IE=7" />

Escaping xml data

2009-08-17T08:23:00.002+02:00

On Shawn's Technical Blog I have read the following article about escaping xml data.

String.Empty vs empty quotes vs String.Length

2009-08-02T17:12:00.003+02:00

The usage of String.Empty is more efficient that the usage of empty quotes.

When using empty quotes an object is created and this produces more assembly code on the execution stack and for string.Empty is NO object created.

The usage of String.Length == 0 is the best. Now there is a numeric compare applied instead of a string compararision, and numeric compare is quicker.

Only what if the string has the value null? So use string.IsNullOrEmpty method

More info: C# Shiznit, Vikram's Blog

Throw; versus Throw e;

2009-08-02T17:02:00.004+02:00

In Coding Standards is the differents between throw and throw e explained.

What is the difference?
The difference is that 'throw;' the original stack trace persists and 'throw ex' truncates the stack trace after the method where the 'throw ex;' is called.

When using 'throw;'?
When in the try{...} a method is called then you must use 'throw;' to take care that you have the original stack trace.

Example:
// Bad!
catch(Exception ex)
{
  Log(ex);
  throw ex;
}

// Good!
catch(Exception)
{
  Log(ex);
  throw;
}

Another alternative is to create a new Exception and pass the current exception as inner exception. The stack trace is shown correctly (complete)

Example:
// Bad!
catch(Exception ex)
{
  Log(ex);
  throw ex;
}

// Good!
catch(Exception)
{
  Log(ex);
  Throw new NotImplementedException(“some extra information”, ex);
}

See for more information Fabrice's weblog, Signs on the Sand, Joteke's Blog

String.Compare or String.ToLower

2009-08-02T16:40:00.003+02:00

// Bad!
Example: (ToLower() creates a temp string)
int id = -1;
string name = "lance hunt";
for(int i=0; i < customerList.Count; i++)
{
  if(customerList[i].Name.ToLower() == name)
  {
    id = customerList[i].ID;
  }
}

// Good! (but not for all cultures)
int id = -1;
string name = "lance hunt";
for(int i=0; i < customerList.Count; i++)
{
  // The “ignoreCase = true” argument performs a
  // case-insensitive compare without new allocation.
  if(String.Compare(customerList[i].Name, name, true)== 0)
  {
    id = customerList[i].ID;
  }
}

// Good! (now also for all cultures)
int id = -1;
string name = "lance hunt";
for (int i = 0; i < customerList.Count; i++)
{
  // The StringComparison.OrdinalIgnoreCase argument performs a
  // case-insensitive compare without new allocation and for several cultures. 
  if (String.Compare(customerList[i].Name, name, StringComparison.OrdinalIgnoreCase) == 0)
  {
    id = customerList[i].ID;
  }
}

Een leuke referentie is de zogenaamde Turkey Test.

Countries depending CurrentCultureInfo

2009-07-27T08:49:00.001+02:00

A nice post about getting countries with taking care of the current culture info.

Refactoring methods

2009-07-01T07:54:00.000+02:00

On Refactoring.com there is published a list with some refactoring rules.

I try myself to read this list and also use this list during programming. And when I optimize some code fragment I want to realize that I am using one of these refactoring methods.

Byte array

2009-06-25T07:46:00.001+02:00

Code snippet for converting a byte array to a string (or vice versa) with or without knowing the Encoding.

LINQ: Join

2009-06-25T07:43:00.003+02:00

The Join operator is an extension method for the String object. With this you can easily create a comma separated string of a list from strings.

On Erwin's Blog you can read an example.

LINQ: Debug Visualizer

2009-06-09T07:44:00.002+02:00

On the blog of Scottgu you will find some instructions for installing a Linq to SQL debug visualizer. With this visualizer installer you can see the relating SQL queries for the Linq statements.

Expresion builders in C#

2009-06-08T07:59:00.001+02:00

On 4GuysFromRolla there is an article about expression builders.

SEO Toolkit

2009-06-05T08:25:00.002+02:00

There is a new nice plugin for IIS 7, the SEO Toolkit. Scottgu describes on his blog, some nice features of the SEO Toolkit

Update 15 july 2009: Nice results of SEO Toolkit.

Link dump: Exception Handling

2009-05-28T07:42:00.007+02:00

I have already post a few blog items about exception handling, but I think it is a difficult subject.

So here some links which provide me some information to get some more information about this subject. And most important how can you add exceptions into an existing application?

General information:

Webservice:

VS2010: Regular Expression Editor

2009-05-26T07:51:00.002+02:00

A couple days ago the beta version of VS2010 is released.

I have not yet installed it on my PC, but I have read about the Regular Expression Editor and I found a Code plex: Editor Samples so maybe you can use this in the near future.

How to start with Unit Testing?

2009-05-26T07:49:00.004+02:00

I do not know how to start with Unit Testing. And I still don't...

So there are several blog items about Unit Testing, see
Unit Testing ASP.NET ASP.NET unit testing has never been this easy - Stefan Sedich's Blog. But what is the best way to start.

Can someone give me a good suggestion?

Update 16 july 2009: I have found a nice list with suggestions on Bugfree.

Browser backbutton in ASP.NET

2009-05-26T07:39:00.003+02:00

The backbutton from the browser does not work often in the way you want in ASP.NET applications. Below some links with information and tweaks relating the back button:

A back button for asp.net pages - Peter's Gekko - CodeBetter.Com - Stuff you need to Code Better!

ASP.NET Browser Back Button - Overclockers Australia Forums

Avoid Back button after logout. - ASP.net - Dotnet Fusion

back button of browser compitible with asp.net application - bytes

dotnetslackers Back Button in ASP.NET

Resource editors

2009-05-25T09:30:00.003+02:00

On the blog entry there are two tools for editing the default resx files for the resources.

The Zeta Resource Editor is a Windows Tool and a Web Tool

Also a useful add-in is the automatically add to resource

LINQ: Any() or Count()

2009-05-07T21:45:00.005+02:00

Update 1 july: Also information about the ToDictionary method

When you have a collection and you want to check if there are items in the collection you can do this

Codefragment 1:


if (lCollection.Count() > 0) {
// do something
}

Codefragment 2:


if (lCollection.Any()) {
// do something
}

When the collection is also an ICollection the Count property is returned otherwise the collection is enumerated an counted for each element. The last one is an expensive operation.

The Any() method begins to iterate over the collection and stops when the condition is true. If you use the variant without the condition, the method iterates over the first element and stops. So code fragment 2 is a better solution qua performance.

LINQ and Deferred Execution

2009-05-07T21:33:00.003+02:00

I was programming with LINQ and again I was forgotten the Deferred Execution of LINQ. I know the LINQ statement will executed when the program is running, but sometimes it is confusing, so I have read Charlie Calvert's Community Blog : LINQ and Deferred Execution
article and hopefully I will reminder it this time.

Difference between Convert.ToBase64String and HttpServerUtility.UrlTokenEncode?

2009-05-06T11:57:00.000+02:00

There are two methods for converting a string to a Base64 value:

But what is the exact differnce between them? And when do you decide the use the Convert or the Encode?

When you are going to transmit a value via a URL the method to use is the: HttpServerUtility.UrlTokenEncode() method,

This method creates a url safe value.

The original base64 string encoding follows a standard definition which uses the following characters:

From:

http://www.ietf.org/rfc/rfc1421.txt

 Value Encoding  Value Encoding  Value Encoding  Value Encoding
      0 A            17 R            34 i            51 z
      1 B            18 S            35 j            52 0
      2 C            19 T            36 k            53 1
      3 D            20 U            37 l            54 2
      4 E            21 V            38 m            55 3
      5 F            22 W            39 n            56 4
      6 G            23 X            40 o            57 5
      7 H            24 Y            41 p            58 6
      8 I            25 Z            42 q            59 7
      9 J            26 a            43 r            60 8
     10 K            27 b            44 s            61 9
     11 L            28 c            45 t            62 +
     12 M            29 d            46 u            63 /
     13 N            30 e            47 v
     14 O            31 f            48 w         (pad) =
     15 P            32 g            49 x
     16 Q            33 h            50 y

                 Printable Encoding Characters
                            Table 1

As you can see there are a few characters in this set that are already used in normal urls. To create url save string the +, / and = characters are substituted for other tokens to create a value which is usable in a URL.

The System.Convert.ToBase64 does not display this behavior which might result in a value which isn't usable in a URL, So when you Encode a value to base64 data which you are going to use in a url use HttpSeverUtility.UrlTokenEncode to create safe values

Clipboard Ring

2009-05-01T12:51:00.003+02:00

In Visual Studio you can use the Clipboard Ring. When you have copied multiple times something with CTRL+C, this is stored on the Clipboard Ring.

With CTRL+SHIFT+V can you browse through the Clipboard Ring.

Events in (Web)UserControls

2009-05-01T09:50:00.000+02:00

On Mats Lycken - Posts about .NET related stuff I have read the following post about Events in (Web)UserControls.
I am a big fan of using (Web)UserControls, but often I forgot to use events... so may be I go use them more now;)