C# Post Json数据

public string Post(string Url, string jsonParas)
    {
        string strURL = Url;

        //创建一个HTTP请求 
        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(strURL);
        //Post请求方式 
        request.Method = "POST";
        //内容类型
        request.ContentType = "application/x-www-form-urlencoded";

        //设置参数，并进行URL编码 

        string paraUrlCoded = jsonParas;//System.Web.HttpUtility.UrlEncode(jsonParas);   

        byte[] payload;
        //将Json字符串转化为字节 
        payload = System.Text.Encoding.UTF8.GetBytes(paraUrlCoded);
        //设置请求的ContentLength  
        request.ContentLength = payload.Length;
        //发送请求，获得请求流 

        Stream writer;
        try
        {
            writer = request.GetRequestStream();//获取用于写入请求数据的Stream对象
        }
        catch (Exception)
        {
            writer = null;
            Console.Write("连接服务器失败!");
        }
        //将请求参数写入流
        writer.Write(payload, 0, payload.Length);
        writer.Close();//关闭请求流

        String strValue = "";//strValue为http响应所返回的字符流
        HttpWebResponse response;
        try
        {
            //获得响应流
            response = (HttpWebResponse)request.GetResponse();
        }
        catch (WebException ex)
        {
            response = ex.Response as HttpWebResponse;
        }

        Stream s = response.GetResponseStream();

        Stream postData = Request.InputStream;
        StreamReader sRead = new StreamReader(s);
        string postContent = sRead.ReadToEnd();
        sRead.Close();

        return postContent;//返回Json数据
    }

//接收
  //获取post过来的json数据结构
                    Stream postData = Request.InputStream;
                    StreamReader sRead = new StreamReader(postData);
                    string postContent = sRead.ReadToEnd();
                    sRead.Close();