Programmatically creating asp.net request and handling response

Hello everyone,
 
I dont know wheter this is the correct forum for asking this question or not , but please help me i am stucked up....

Please let me know how to get part of response generated from the url.

I have written this code:
 Collapse using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Net;
using Syst ...