客户端调用接口

public void CallBackCheck(string barcode, string ticketcount, string zybbillno)
        {
　　　　　　　　 //接口参数的定义   json格式
            string json = "{"checkNo": "" + barcode + "","checkOrderType": "1","operateTime": "" + DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss") + "","orderDetailId": "" + zybbillno + "","ticketCount": "" + ticketcount + ""}";
            string code = "checkNo=" + barcode;
               //接口签名验证
            string sign = MD5Encrypt(code);
　　　　　　　　 //从配置文件获取接口的地址
            string url = TwiConfigHelper.GetAppSettingValue("zybQ");
            //string postData = string.Format("sdk=13812095997&code=wuxi0303&phones={0}&msg={1}&resulttype=text",
　　　　　　　　 //需要向接口传递的参数
            string postData = string.Format("noticeParam={0}&noticeType=1&sign={1}",
                json,
                sign
            );

            try
            {
                HttpWebRequest httpWebRequest = (HttpWebRequest)WebRequest.Create(url);
                httpWebRequest.ContentType = "application/x-www-form-urlencoded";
                httpWebRequest.Method = "POST";
                httpWebRequest.Timeout = 20000;
                byte[] btBodys = Encoding.UTF8.GetBytes(postData);
                httpWebRequest.ContentLength = btBodys.Length;
                httpWebRequest.GetRequestStream().Write(btBodys, 0, btBodys.Length);
                HttpWebResponse httpWebResponse = (HttpWebResponse)httpWebRequest.GetResponse();
                StreamReader streamReader = new StreamReader(httpWebResponse.GetResponseStream());
                string responseContent = streamReader.ReadToEnd();
                httpWebResponse.Close();
                streamReader.Close();
                httpWebRequest.Abort();
                httpWebResponse.Close();
                //MessageBox.Show(responseContent);
            }
            catch (Exception ex)
            {
                //MessageBox.Show(ex.Message);
            }
        }