ASP.NET后台手动调用POST提交并获取返回值，用于短信平台接口

                                短信平台              
[解决办法]

        public static string PostDataGetHtml(string uri, string postData)
        {
            try
            {
                byte[] data = Encoding.UTF8.GetBytes(postData);

                Uri uRI = new Uri(uri);
                HttpWebRequest req = WebRequest.Create(uRI) as HttpWebRequest;
                req.Method = "POST";
                req.KeepAlive = true; 
 
                req.ContentType = "application/x-www-form-urlencoded";
                req.ContentLength = data.Length;
                req.AllowAutoRedirect = true;

                Stream outStream = req.GetRequestStream();
                outStream.Write(data, 0, data.Length);
                outStream.Close();

                HttpWebResponse res = req.GetResponse() as HttpWebResponse;
                Stream inStream = res.GetResponseStream();
                StreamReader sr = new StreamReader(inStream, Encoding.UTF8);
                string htmlResult = sr.ReadToEnd();

                return htmlResult;
            }
            catch (Exception ex)
            {
                return "网络错误：" + ex.Message.ToString();
            }
        }