İpucu: HttpWebRequest ile https

HttpWebRequest sınıfı ile https üzerinden veri alışverişinde bulunduysanız muhakkak karşılaşmışsınızdır.

"The underlying connection was closed: Could not establish trust relationship for the SSL/TLS secure channel."

Bu durumu aşağıdaki event’a anonim bir delegate tanımlayarak bypass edebiliyoruz.

            System.Net.ServicePointManager.ServerCertificateValidationCallback += delegate
                                                                            (object sender, X509Certificate certificate, X509Chain chain, 
                                                                            SslPolicyErrors sslPolicyErrors)
                                                                            { return true; };
            
            var parameters = "go=1";

            var cred = new NetworkCredential();
            cred.Password = "demo"
            cred.UserName = "admin"

            var request = (HttpWebRequest)HttpWebRequest.Create("https://www.google.com");
            request.AllowAutoRedirect = false;
            request.ContentType = "application/x-www-form-urlencoded";
            request.Credentials = cred;
            request.Method = "POST";
            request.UserAgent = "Vargonen/0.1";
            request.ContentLength = parameters.Length;

            var reqStream = request.GetRequestStream();
            reqStream.Write(parameters, 0, parameters.Length);   
            reqStream.Close();

            var response = (HttpWebResponse)request.GetResponse();
            var sr = new StreamReader(response.GetResponseStream());
            var htmlText = sr.ReadToEnd().Trim();

http://msdn.microsoft.com/en-us/library/system.net.servicepointmanager.servercertificatevalidationcallback.aspx