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Archive for June, 2009

Get size of a file placed on any web server

Posted by Virendra Dugar on June 25, 2009

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This post demonstrate you that how can you find the size of file which is placed on any webserver.

I have placed a label, a textbox and a button on an aspx page.  Textbox will be having valid URL with the file name.

On button click, Place this code


That’s it..



Posted in ASP.NET | Tagged: | Leave a Comment »

Using C# and VB.NET classes together in the App_Code folder

Posted by Virendra Dugar on June 15, 2009

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Learn new ASP.NET Core 1.0 Framework

In ASP.NET 2.0 one can mix web forms coded in C# and VB.NET together in a single web site. This works great for web forms. However if you want to code classes from App_Code folder in different languages? Such mixing of classes coded in different languages is not allowed with default settings. You can, however,configure your web site to get this done. This article is going to explain you that how one can do that.

Creating sub folders and classes

First of all, Create a new webSite in VS.NET 2005. Add App_Code folder to it. You can do so easily by right clicking on the web site in the Solution Explorer and choosing Add ASP.NET Folder” option (see below).

Different Language

Once you add the App_Code folder add two class files – Class1.cs and Class2.vb. Note that one class file must be in C# where as the other must be in VB.NET. Add the following code in Class1.cs.
C# Code

Similarly, add the following code in Class2.vb.


Both of these classes contain a method called HelloWorld() that simply return a string to the caller.

Now try compiling the web site. What happens? You will get an error as shown below:

Error 1 The files ‘/VBandCSharptogether/App_Code/Class2.vb’  and ‘/VBandCSharptogether/App_Code/Class1.cs’ use a
different language, which is not allowed since they need to be compiled together.

The error message bluntly tells us that you can not use different coding languages for the classes in App_Code folder. Fortunately, there is a way to get out of this trap. Firstly you need to put C# and VB.NET classes in separate sub-folders under App_Code. Secondly you need to add some markup in the web.config file to tell ASP.NET compiler about your intention.

<codeSubDirectories> Section

Create two folders under App_Code filder named CSCode and VBCode. Move Class1.cs inside CSCode folder and Class2.vb inside VBCode folder.

Add a web.config file to your web site and add the following markup to it:

Web Config Code

Here, we added <compilation> section. The <codeSubDirectories> section defines a set of sub-directories relative to App_Code folder that are compiled at run time. The directoryName attribute points to the sub-folder of App_code. Each sub folder is compiled separately and hence each can have classes coded in different languages. We added our CSCode and VBCode folder in this section. This way the compiler will compile classes from CSCode and VBCode folders separately.

After configuring the web site try to compile it. This time it compiles successfully.


Quick summary of what’s changed in ASP.NET Core 1.0

Posted in ASP.NET, C#, VB.NET | Tagged: , , | 18 Comments »

Exception Handling Best Practices in .NET

Posted by Virendra Dugar on June 10, 2009

Check out this cool article on code project by Daniel Turini on best practice of Exception Handling in .NET.

A very good article indeed.


Posted in ASP.NET | Tagged: | Leave a Comment »

Textbox with autopostback and regularexpression validator

Posted by Virendra Dugar on June 5, 2009

Quick summary of what’s changed in ASP.NET Core 1.0

Suppose you have a textbox on your aspx page that has a autopostback set to true and It makes a call to server side function on TextChanged Event. You have also placed a RegularExpression Validator which validates the textbox value against the validation expression.

For example: You want to allow only numeric characters in the text box and you have placed a regular expression validator to achieve this. And you also want to do some server side operation on text change.

 TextBox and RegularExpression Validator
When you run the application and if you type any alphabets in the textbox, the regular expression validates the input, it shows the error message but the weird thing is it also does the post back and call the server side text change event and error message is gone. This is what you don’t want. TextChange event must be called only when inputs are correct. Then how do you do this?

A very simple solution. Just set the CausesValidation="true" for the textbox and you are done.


Learn new ASP.NET Core 1.0 Framework

Posted in ASP.NET | Tagged: | 11 Comments »

No need to type runat=”server” now

Posted by Virendra Dugar on June 1, 2009

If you are using Visual Studio 2005 or 2008, for every or Html control, you need to explicity write runat=”server” attribute. Sometimes I really wonder, why I have to write this attribute for every control as most of time I want to access controls on server side. Is n’t is tedious task? It should be added automatically. But it’s not possible with Visual Studio 2005 or 2008.

Well, we have a good news now. Now there is no need to type runat=”server“. It does not mean that It has been removed. Nope.. it’s get added automatically in VS 2010. Wow.. amazing..

In VS 2010, Microsoft has added hundereds of new code snippest for HTML, JavaScript and for ASPX.  If you want to place a textbox on the page, type tb and press Tab. Wow… You will see something like this..

<asp:TextBox ID="TextBox1" runat="server"/>

Type req and press Tab. Boom…

<asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ControlToValidate="TextBox1" ErrorMessage="errormessage"></asp:RequiredFieldValidator>

There are lots of other code snippest almost for every control. Even for HTML tag also like table. Is n’t is cool?

Check out this video by Jeff king on new web development features of VS 2010.


Posted in ASP.NET 4.0 | Tagged: | Leave a Comment »

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