For production applications, developers often end up spending a lot more time and code on this task than we would like. NET page framework, it was important to try and make the task of validating input a lot easer than it has been in the past.

In HTML 3.2, validating data is a difficult process.

Locate the Operator option and write Data Type Check(alternatively you can also select from drop down)in it .

Again locate the Type option and write Integer in it .

I have inserted a request on Visual Studio User Voice (the portal where you can ask for improvements on .

NET products) in order to add the property Validation Group to IValidator interface and change accordingly the implementation of the method responsible for getting all validators with a particular validation group (Page.

Actually, that's all we need to test the most basic part of the Required Field Validator. Validation is only performed serverside if necessary!

I'm sure that all the attributes of the controls makes sense by now, so I won't go into details about them. You should see something like this: If your browser supports Java Script, which most modern browers do, then you will notice that the page is not being posted back to the server - the validation is performed clientside! To see how it feels, you can add enableclientscript="false" to the Required Field Validator and try again.

We will change this by adding an onclick event to it: As you will notice, we check whether or not the page is valid, before we do anything.

This is very important, since this code WILL be reached if the clientside validation is not used, for some reason.

Anthony Moore Microsoft Corporation July 2000 Updated March 2002 Summary: Provides a brief overview of the validation framework in ASP.

NET and walks through an example of adding validation to a page.

Now you will see the browser posting back to the server, but the result will be the same - the validator still works!