C# 后台模拟前台post发送json数据

 public static string PostMoths(string url, string param)    {        string strURL = url;        System.Net.HttpWebRequest request;        request = (System.Net.HttpWebRequest)WebRequest.Create(strURL);        request.Method = "POST";        request.ContentType = "application/json;charset=UTF-8";        string paraUrlCoded = param;        byte[] payload;        payload = System.Text.Encoding.UTF8.GetBytes(paraUrlCoded);        request.ContentLength = payload.Length;        Stream writer = request.GetRequestStream();        writer.Write(payload, 0, payload.Length);        writer.Close();        System.Net.HttpWebResponse response;        response = (System.Net.HttpWebResponse)request.GetResponse();        System.IO.Stream s;        s = response.GetResponseStream();        string StrDate = "";        string strValue = "";        StreamReader Reader = new StreamReader(s, Encoding.UTF8);        while ((StrDate = Reader.ReadLine()) != null)        {            strValue += StrDate + "\r\n";        }        return strValue;    }