(C#) Get the Server Certificate, Certificate Chain, and Root CA Certificate

Demonstrates how to get the HTTP server certificate, its certificate chain, and the root CA certificate.

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// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

Chilkat.Http http = new Chilkat.Http();

// We're getting the SSL/TLS certificate, so make sure to connect to the SSL/TLS port (443).
Chilkat.Cert sslCert = http.GetServerSslCert("nationalgeographic.com",443);
if (http.LastMethodSuccess == false) {
    Debug.WriteLine(http.LastErrorText);
    return;
}

// Note: Prior to v9.5.0.50, this method would fail if the certificate chain could not 
// be completed to the root.  Starting in v9.5.0.50, the incomplete certificate chain 
// will be returned.  The certificate chain's ReachesRoot property can be examined to 
// see if the chain was completed to the root.
Chilkat.CertChain certChain = sslCert.GetCertChain();
if (sslCert.LastMethodSuccess == false) {
    Debug.WriteLine(sslCert.LastErrorText);

    return;
}

int i = 0;
int numCerts = certChain.NumCerts;
while (i < numCerts) {
    Chilkat.Cert cert = certChain.GetCert(i);
    Debug.WriteLine("SubjectDN " + Convert.ToString(i) + ": " + cert.SubjectDN);
    Debug.WriteLine("IssuerDN " + Convert.ToString(i) + ": " + cert.IssuerDN);

    i = i + 1;
}

// If the certificate chain reaches the root CA cert, then the last cert in the chain
// is the root CA cert.
if (certChain.ReachesRoot == true) {
    Chilkat.Cert caCert = certChain.GetCert(numCerts - 1);
    Debug.WriteLine("CA Root Cert: " + caCert.SubjectDN);

}