ASP.NET Post方式提交

public static string SendMsg(string fxPhone, string fxPassword, string toPhone, string msg)
        {
            try
            {
                string url = "u=" + fxPhone + "&";
                url = url + "p=";
                url = url + fxPassword + "&";
                url = url + "to=";
                url = url + toPhone + "&";
                url = url + "m=" + msg;

                string formUrl = "http://quanapi.sinaapp.com/fetion.php";
                string formData = url;                               //提交的参数

                //注意提交的编码 这边是需要改变的 这边默认的是Default：系统当前编码
                byte[] postData = Encoding.UTF8.GetBytes(formData);

                // 设置提交的相关参数 
                HttpWebRequest request = WebRequest.Create(formUrl) as HttpWebRequest;
                Encoding myEncoding = Encoding.UTF8;
                request.Method = "POST";
                request.KeepAlive = false;
                request.AllowAutoRedirect = true;
                request.ContentType = "application/x-www-form-urlencoded";
                request.UserAgent = "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727; .NET CLR  3.0.04506.648; .NET CLR 3.5.21022; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)";
                request.ContentLength = postData.Length;

                // 提交请求数据 
                System.IO.Stream outputStream = request.GetRequestStream();
                outputStream.Write(postData, 0, postData.Length);
                outputStream.Close();

                HttpWebResponse response;
                Stream responseStream;
                StreamReader reader;
                string srcString;
                response = request.GetResponse() as HttpWebResponse;
                responseStream = response.GetResponseStream();
                reader = new System.IO.StreamReader(responseStream, Encoding.GetEncoding("UTF-8"));
                srcString = reader.ReadToEnd();
                string result = srcString;   //返回值赋值
                reader.Close();
                return result;
            }
            catch
            {
                return "error";
            }
        }