//HTTP post JSON 參數
private string HttpPost(string Url, Object ticket)
{
DataContractJsonSerializer serializer = new DataContractJsonSerializer(ticket.GetType());
MemoryStream stream = new MemoryStream();
serializer.WriteObject(stream, ticket);
byte[] dataBytes = new byte[stream.Length];
stream.Position = 0;
stream.Read(dataBytes, 0, (int)stream.Length);
string param = Encoding.UTF8.GetString(dataBytes);
byte[] bs = Encoding.ASCII.GetBytes(param);
HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create(Url);
req.Method = "POST";
req.ContentType = "application/x-www-form-urlencoded";
req.ContentLength = bs.Length;
using (Stream reqStream = req.GetRequestStream())
{
reqStream.Write(bs, 0, bs.Length);
}
HttpWebResponse hwr = req.GetResponse() as HttpWebResponse;
System.IO.StreamReader myreader = new System.IO.StreamReader(hwr.GetResponseStream(), Encoding.UTF8);
string responseText = myreader.ReadToEnd();
return responseText;
}

導入對應的dll , Object參數可以隨意，實體類傳什麽，json參數就是什麽。

c# HttpWebRequest 模擬HTTP post 傳遞JSON參數