} // End Sub CertificateFileChanged

        public static System.Security.Cryptography.X509Certificates.X509Certificate2 ServerCertificateSelector(
            System.Collections.Concurrent.ConcurrentDictionary <string, CertHackStore> certs
            , Microsoft.AspNetCore.Connections.ConnectionContext connectionContext
            , string name)
        {
            if (certs != null && certs.Count > 0)
            {
                // return certs.GetEnumerator().Current.Value;
                // return System.Linq.Enumerable.FirstOrDefault(certs);
                foreach (System.Collections.Generic.KeyValuePair <string, CertHackStore> thisCert in certs)
                {
                    System.Console.WriteLine("SNI Name: {0}", name);

                    return(thisCert.Value.Certificate);
                } // Next thisCert
            }     // End if (certs != null && certs.Count > 0)


            // CertHackStore cert;
            // if (name != null && certs.TryGetValue(name, out cert))
            // {
            //     return cert.NewCertificate;
            // }

            throw new System.IO.InvalidDataException("No certificate for name \"" + name + "\".");
        } // End Function ServerCertificateSelector