CustomHttp.test is the name of the file that launches the HTTPHandler.

First Create a class 

Answer:

This is a simple a .NET Interview question .Its a two step process.

First create a class which implements Ihttphandler
 

public class clsHttpHandler : IHttpHandler
{
    public bool IsReusable
    {
        get { return true; }
    }
    public void ProcessRequest(HttpContext context)
    {
       // Put implementation here.
    }
}

Step 2 make a entry in the web.config file.

<httpHandlers>
<add verb="*" path="*.gif" type="clsHttpHandler"/>
</httpHandlers>

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