public static void SetSessionID(string url)
        {
            Uri uri = new Uri(url);
            WebRequest request = WebRequest.Create(uri);
            request.Method = "POST";
            request.ContentType = "application/x-www-form-urlencoded";
            request.Headers.Add("Accept-Language", "zh-cn");
            request.Headers.Add("Accept-Encoding", "gzip,deflate");
            

            WebResponse response = request.GetResponse();

            foreach (string item in response.Headers.Keys)
            {
                if (item == "Set-Cookie")
                {
                    string[] data = response.Headers.GetValues(item);
                    foreach (string d in data)
                    {
                        if (d.ContainsUL("SessionID"))
                        {
                            SessionID = d;
                            return;
                        }
                    }
                }
            }