asp.net C# 实现模拟请求（webrequest）

HttpWebRequest webRequest = (HttpWebRequest)HttpWebRequest.Create(uri );
           webRequest.ContentType = "application/x-www-form-urlencoded;charset=gb2312";
           webRequest.Method = "POST";
           string postData = string.Format("appname={0}&channel={1}",parameter1,parameter2);
           byte[] bs = Encoding.Default.GetBytes(postData);
           using (Stream s = webRequest.GetRequestStream())
           {
               s.Write(bs, 0, bs.Length);
           }
           JSAppInfo jsApp = new JSAppInfo();
           using (WebResponse wr = webRequest.GetResponse())
           {
               StreamReader sr = new StreamReader(wr.GetResponseStream());
               string str = sr.ReadToEnd();
               jsApp = JsonConvert.DeserializeObject<JSAppInfo>(str);
               sr.Close();
               sr.Dispose();
           }