C#请求接口

eg：

System.Net.WebClient WebClientObj = new System.Net.WebClient();
System.Collections.Specialized.NameValueCollection PostVars = new System.Collections.Specialized.NameValueCollection();
PostVars.Add("userid", userid);


byte[] byRemoteInfo = null;
string url = "http://~";
byRemoteInfo = WebClientObj.UploadValues(url, "POST", PostVars);
string str = System.Text.Encoding.UTF8.GetString(byRemoteInfo);