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.

Download: Chilkat .NET Assemblies

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

bool success;

//  LoadFromFile will load virtually any certificate format file.
//  It will auto-recognize the format and load appropiately.
success = cert.LoadFromFile("/Users/chilkat/testData/cer/chilkat.cer");
if (success != true) {
    textBox1.Text += cert.LastErrorText + "\r\n";
    return;
}

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

pubkey = cert.ExportPublicKey();
if (pubkey == null ) {
    textBox1.Text += cert.LastErrorText + "\r\n";
    return;
}

//  Save to various formats:
success = pubkey.SaveOpenSslDerFile("/Users/chilkat/testData/pubkeys/chilkat_openSsl.der");
if (success != true) {
    textBox1.Text += pubkey.LastErrorText + "\r\n";

    return;
}

success = pubkey.SaveOpenSslPemFile("/Users/chilkat/testData/pubkeys/chilkat_openSsl.pem");
if (success != true) {
    textBox1.Text += pubkey.LastErrorText + "\r\n";

    return;
}

success = pubkey.SaveRsaDerFile("/Users/chilkat/testData/pubkeys/chilkat_rsa.der");
if (success != true) {
    textBox1.Text += pubkey.LastErrorText + "\r\n";

    return;
}

success = pubkey.SaveXmlFile("/Users/chilkat/testData/pubkeys/chilkat.xml");
if (success != true) {
    textBox1.Text += pubkey.LastErrorText + "\r\n";

    return;
}

textBox1.Text += "Public key exported to all file formats." + "\r\n";