HttpWebRequest 登陆网站问题

Question

为什么我这样弄之后 登陆不上 然后我用html试图看返回数据上面显示浏览器不支持 javascript啊public void Login(string UserName, string UserPwd, string LoginUrl, out string Txt)
        {
            try
            {
                //定义Cookie容器
                CookieContainer CookieArray = new CookieContainer();                //创建Http请求
                HttpWebRequest LoginHttpWebRequest = (HttpWebRequest)WebRequest.Create(LoginUrl);                //登录数据
                string LoginData = "email=" + UserName + "&password=" + UserPwd + "http://www.renren.com/SysHome.do";
                //数据被传输类型
                LoginHttpWebRequest.ContentType = "application/x-www-form-urlencoded";
                //数据长度
                LoginHttpWebRequest.ContentLength = LoginData.Length;
                //数据传输方法 get或post
                LoginHttpWebRequest.Method = "POST";
                //设置HttpWebRequest的CookieContainer为刚才建立的那个CookieArray  
                LoginHttpWebRequest.CookieContainer = CookieArray;
                //获取登录数据流
                Stream myRequestStream = LoginHttpWebRequest.GetRequestStream();
                //StreamWriter
                StreamWriter myStreamWriter = new StreamWriter(myRequestStream);
                //把数据写入HttpWebRequest的Request流  
                myStreamWriter.Write(LoginData);                //关闭打开对象     
                myStreamWriter.Close();                myRequestStream.Close();                //新建一个HttpWebResponse     
                HttpWebResponse myHttpWebResponse = (HttpWebResponse)LoginHttpWebRequest.GetResponse();                //获取一个包含url的Cookie集合的CookieCollection     
                myHttpWebResponse.Cookies = CookieArray.GetCookies(LoginHttpWebRequest.RequestUri);                WebHeaderCollection a = myHttpWebResponse.Headers;                Stream myResponseStream = myHttpWebResponse.GetResponseStream();                StreamReader myStreamReader = new StreamReader(myResponseStream);                Txt = myStreamReader.ReadToEnd();                //把数据从HttpWebResponse的Response流中读出     
                myStreamReader.Close();                myResponseStream.Close();
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }