(.NET Core C#) Export Digital Certificate's Public Key

The ExportPublicKey method can be called to get a certificate's public key. It can then be saved to any of a number of formats: (1) OpenSSL DER, (2) OpenSSL PEM, (3) RSA DER, (4) XML.

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Chilkat.Cert cert = new Chilkat.Cert();

// LoadFromFile will load virtually any certificate format file.
// It will auto-recognize the format and load appropiately.
bool success = cert.LoadFromFile("/Users/chilkat/testData/cer/chilkat.cer");
if (success != true) {
    Debug.WriteLine(cert.LastErrorText);
    return;
}

// Get the public key:
Chilkat.PublicKey pubkey = null;

pubkey = cert.ExportPublicKey();
if (cert.LastMethodSuccess == false) {
    Debug.WriteLine(cert.LastErrorText);
    return;
}

// Save to various formats:
success = pubkey.SaveDerFile(false,"/Users/chilkat/testData/pubkeys/chilkat_pkcs8.der");
if (success != true) {
    Debug.WriteLine(pubkey.LastErrorText);

    return;
}

success = pubkey.SavePemFile(false,"/Users/chilkat/testData/pubkeys/chilkat.pem");
if (success != true) {
    Debug.WriteLine(pubkey.LastErrorText);

    return;
}

success = pubkey.SaveDerFile(true,"/Users/chilkat/testData/pubkeys/chilkat_pkcs1.der");
if (success != true) {
    Debug.WriteLine(pubkey.LastErrorText);

    return;
}

success = pubkey.SaveXmlFile("/Users/chilkat/testData/pubkeys/chilkat.xml");
if (success != true) {
    Debug.WriteLine(pubkey.LastErrorText);

    return;
}

Debug.WriteLine("Public key exported to all file formats.");