I think your problem lies in getting the datastream, here is an example adapted from a CodeProject article:
private static void get_cotents(string contents_url)
{
byte[] buffer = new byte[1024];
HttpWebRequest WebReq = (HttpWebRequest)WebRequest.Create(contents_url);
WebReq.Method = "POST";
WebReq.ContentType = "application/x-www-form-urlencoded";
WebReq.ContentLength = buffer.Length;
Stream PostData = WebReq.GetRequestStream();
PostData.Write(buffer, 0, buffer.Length);
PostData.Close();
HttpWebResponse WebResp = (HttpWebResponse)WebReq.GetResponse();
Console.WriteLine(WebResp.StatusCode);
Console.WriteLine(WebResp.Server);
Stream datastream = WebResp.GetResponseStream();
StreamReader answer = new StreamReader(datastream);
Console.WriteLine(answer.ReadToEnd());
datastream.Close();
answer.Close();
}
I think you can finish the rest of the code yourself ...