模拟登录 asp.net ajax页面有关问题

protected void Page_Load(object sender, EventArgs e)    {        //创建请求连接信息        string url = "http://localhost:1393/MoNiDengLu/Login.aspx";        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);        request.Method = "POST";        request.ContentType = "application/x-www-form-urlencoded";        string userName = "1";        string passWord = "1";        string data = "Button1=Button&ScriptManager1=UpdatePanel1%7CButton1&TextBox1="+userName+"&TextBox2="+passWord+"&__ASYNCPOST=true&__EVENTARGUMENT=&__EVENTTARGET=&__EVENTVALIDATION=%2FwEWBALmityHBALs0bLrBgLs0fbZDAKM54rGBlRC8oDQj1W%2FTfi7ZqiSWOmb%2FD5y&__VIEWSTATE=%2FwEPDwUKMTc4MDEwMTAwNA9kFgICAw9kFgICAw9kFgJmD2QWAgIHDw8WAh4EVGV4dAUM55m75b2V5oiQ5YqfZGRk5YHabszuzefMIAFShVj9GKGye74%3D";        request.ContentLength = data.Length;        request.AllowAutoRedirect = true;                    //将POST信息附加到请求流中        StreamWriter writer = new StreamWriter(request.GetRequestStream(), Encoding.ASCII);        writer.Write(data);        writer.Flush();        //获取响应，并设置响应编码        HttpWebResponse response = (HttpWebResponse)request.GetResponse();        string encoding = response.ContentEncoding;        if (encoding == null || encoding.Length < 1)        {            encoding = "utf-8"; //默认编码        }        //读取响应流        StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.GetEncoding(encoding));        data = reader.ReadToEnd();        Response.Write(data);        reader.Dispose();        response.Close();    }