PRivate static void SetCertificatePolicy()        {            if( ServicePointManager.ServerCertificateValidationCallback==null){                ServicePointManager.ServerCertificateValidationCallback += RemoteCertificateValidate;            }        }        /// <summary>          /// 遠程證書驗證，固定返回true         /// </summary>          private static bool RemoteCertificateValidate(object sender, X509Certificate cert,            X509Chain chain, SslPolicyErrors error)        {            return true;        }