Как правильно отправить формдату на сайт? Конкретный пример - C#

public static string LogIn(string login, string password, string uni)
        {
            ASCIIEncoding encoding = new ASCIIEncoding();
            string postData = "username="+login+"&password="+password+"&uni="+uni;
            byte[] byteArray = encoding.GetBytes(postData);
            HttpWebRequest myRequest = (HttpWebRequest)WebRequest.Create("http://xgame-online.com");
            myRequest.Headers.Add("Cache-Control", "max-age=0");
            myRequest.UserAgent = "Saldoran's xgameclient v0.1";
            myRequest.ContentType = "application/x-www-form-urlencoded";
            myRequest.Referer = "http://xgame-online.com/";
            myRequest.Method = "POST";
            //myRequest.Connection = "keep-alive";
            myRequest.ContentType = "text/html";
            myRequest.ContentLength = byteArray.Length;
            Stream dataStream = myRequest.GetRequestStream();
            dataStream.Write(byteArray, 0, byteArray.Length);
            dataStream.Close();
            WebResponse response = myRequest.GetResponse();
            dataStream = response.GetResponseStream();
            StreamReader reader = new StreamReader(dataStream);             
            string result= reader.ReadToEnd();
            reader.Close();
            dataStream.Close();
            response.Close();            
            return  result;
        }