ASP.NET

    protected override void OnInit(EventArgs e)
    {

        string formText = @"
<script runat=""server"">

    protected void Page_Load(object sender, EventArgs e)
    {
        
    }

    protected void Button1_Click(object sender, EventArgs e)
    {
        ((Button)sender).Text = TextBox1.Text;
    }
</script>

<asp:TextBox ID=""TextBox1"" runat=""server""></asp:TextBox>
<asp:Button ID=""btn1"" runat=""server"" onclick=""Button1_Click""></asp:Button>
";
        Control dControl = Page.ParseControl(formText);

        Page.Form.Controls.Add(dControl);

        base.OnInit(e);
    }

private string ProcessFormPOST(string strURL, string strFormData)
       {
           try
           {
               //string strViewstate = GetInitialViewState(strURL);
               //strViewstate = System.Web.HttpUtility.UrlEncode(strViewstate);
               //strFormData += "&__VIEWSTATE=" + strViewstate;

               byte[] buffer = Encoding.UTF8.GetBytes(strFormData);
               string proxy = null;

               System.Net.HttpWebRequest req = (System.Net.HttpWebRequest)System.Net.WebRequest.Create(strURL);

               req.Method = "POST";
               req.ContentType = "application/x-www-form-urlencoded";
               req.ContentLength = buffer.Length;
               req.Proxy = new System.Net.WebProxy(proxy, true); // ignore for local addresses
               req.CookieContainer = new System.Net.CookieContainer(); // enable cookies

               System.IO.Stream reqst = req.GetRequestStream(); // add form data to request stream
               reqst.Write(buffer, 0, buffer.Length);
               //reqst.Flush();
               reqst.Close();

               System.Net.HttpWebResponse res = (System.Net.HttpWebResponse)req.GetResponse(); // send request, get response

               System.IO.Stream resst = res.GetResponseStream(); // display HTTP response
               System.IO.StreamReader sr = new System.IO.StreamReader(resst);

               return sr.ReadToEnd();
           }
           catch (Exception ex)
           {
               throw ex;
           }
       }