//using (System.Net.WebClient wc = new System.Net.WebClient())

//{//    wc.Encoding = Encoding.GetEncoding("GB2312");//    NameValueCollection postData = new NameValueCollection();//    postData.Add("UserIDText", userId.ToString());//    postData.Add("UserNameText", userName);//    postData.Add("ContentText", HttpUtility.UrlEncode(content,wc.Encoding));//    postData.Add("UrlText", url);//    wc.Headers.Add(HttpRequestHeader.ContentEncoding, "gb23112");//    wc.Headers.Add(HttpRequestHeader.ContentType, "application/x-www-form-urlencoded");//    wc.UploadValues(new Uri(postUrl),"POST", postData);//}Encoding myEncoding = Encoding.GetEncoding("gb2312");string param = "UserIDText=" + HttpUtility.UrlEncode(userId.ToString(), myEncoding)    + "&" + "UserNameText=" + HttpUtility.UrlEncode(userName, myEncoding)    + "&" + "ContentText=" + HttpUtility.UrlEncode(content, myEncoding)    + "&" + "UrlText=" + HttpUtility.UrlEncode(url, myEncoding);byte[] postBytes = Encoding.ASCII.GetBytes(param);HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create(postUrl);req.Method = "POST";req.ContentType = "application/x-www-form-urlencoded;charset=gb2312";req.ContentLength = postBytes.Length;using (Stream reqStream = req.GetRequestStream()){    reqStream.Write(postBytes, 0, postBytes.Length);}using (WebResponse wr = req.GetResponse()){    //在这里对接收到的页面内容进行处理}