private string GetHttpWebRequest(string url)
        {
            HttpWebResponse result;
            string strHTML = string.Empty;
            try
            {
                Uri uri = new Uri(url);
                WebRequest webReq = WebRequest.Create(uri);
                WebResponse webRes = webReq.GetResponse();

                HttpWebRequest myReq = (HttpWebRequest)webReq;
                myReq.UserAgent = "User-Agent:Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; .NET CLR 1.0.3705";
                myReq.Accept = "*/*";
                myReq.KeepAlive = true;
                myReq.Headers.Add("Accept-Language", "zh-cn,en-us;q=0.5");
                result = (HttpWebResponse)myReq.GetResponse();
                Stream receviceStream = result.GetResponseStream();
                StreamReader readerOfStream = new StreamReader(receviceStream, System.Text.Encoding.GetEncoding("utf-8"));
                strHTML = readerOfStream.ReadToEnd();
                readerOfStream.Close();
                receviceStream.Close();
                result.Close();
            }
            catch
            {
                Uri uri = new Uri(url);
                WebRequest webReq = WebRequest.Create(uri);
                HttpWebRequest myReq = (HttpWebRequest)webReq;
                myReq.UserAgent = "User-Agent:Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; .NET CLR 1.0.3705";
                myReq.Accept = "*/*";
                myReq.KeepAlive = true;
                myReq.Headers.Add("Accept-Language", "zh-cn,en-us;q=0.5");
                try
                {
                    result = (HttpWebResponse)myReq.GetResponse();
                }
                catch (WebException ex)
                {
                    result = (HttpWebResponse)ex.Response;
                }
                Stream receviceStream = result.GetResponseStream();
                StreamReader readerOfStream = new StreamReader(receviceStream, System.Text.Encoding.GetEncoding("gb2312"));
                strHTML = readerOfStream.ReadToEnd();
                readerOfStream.Close();
                receviceStream.Close();
                result.Close();
            }
            return strHTML;
        }