public static string PostData(string data, string method, string postUrl)
        {
            HttpWebRequest request;
            HttpWebResponse response;
            ASCIIEncoding encoding = new ASCIIEncoding();
            request = WebRequest.Create(postUrl) as HttpWebRequest;
            request.ProtocolVersion = HttpVersion.Version10;
            request.AllowAutoRedirect = true;
            request.KeepAlive = true;
            request.Headers.Add("Accept-Language", "zh-cn");
            request.Accept = "image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/xaml+xml, application/vnd.ms-xpsdocument, application/x-ms-xbap, application/x-ms-application, application/x-shockwave-flash, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*";
            request.UserAgent = "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.2; Trident/4.0; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; InfoPath.2; CIBA; .NET4.0C; .NET4.0E)";
            request.Method = "GET";
            if (method == "post")
            {
                byte[] b = encoding.GetBytes(data);
                request.ContentType = "application/x-www-form-urlencoded";
                request.ContentLength = b.Length;
                request.Method = "POST";
                using (Stream stream = request.GetRequestStream())
                {
                    stream.Write(b, 0, b.Length);
                }
            }

            string html = string.Empty;
            
            try
            {
                //获取服务器返回的资源
                using (response = request.GetResponse() as HttpWebResponse)
                {
                    using (StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.GetEncoding("utf-8")))
                    {
                        html = reader.ReadToEnd();
                    }
                }
            }
            catch (WebException wex)
            {
                WebResponse wr = wex.Response;
                using (Stream st = wr.GetResponseStream())
                {
                    using (StreamReader sr = new StreamReader(st, System.Text.Encoding.Default))
                    {
                        html = sr.ReadToEnd();
                    }
                }
            }
            catch (Exception ex)
            {
                html ="发生异常\n\r" + ex.Message;
            }
            return html;
        }