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.

<?php

$cert = new COM("Chilkat.Cert");

//  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) {
    print $cert->lastErrorText() . "\n";
    exit;
}

//  Get the public key:

// pubkey is a Chilkat.PublicKey
$pubkey = $cert->ExportPublicKey();
if (is_null($pubkey)) {
    print $cert->lastErrorText() . "\n";
    exit;
}

//  Save to various formats:
$success = $pubkey->SaveOpenSslDerFile('/Users/chilkat/testData/pubkeys/chilkat_openSsl.der');
if ($success != true) {
    print $pubkey->lastErrorText() . "\n";

    exit;
}

$success = $pubkey->SaveOpenSslPemFile('/Users/chilkat/testData/pubkeys/chilkat_openSsl.pem');
if ($success != true) {
    print $pubkey->lastErrorText() . "\n";

    exit;
}

$success = $pubkey->SaveRsaDerFile('/Users/chilkat/testData/pubkeys/chilkat_rsa.der');
if ($success != true) {
    print $pubkey->lastErrorText() . "\n";

    exit;
}

$success = $pubkey->SaveXmlFile('/Users/chilkat/testData/pubkeys/chilkat.xml');
if ($success != true) {
    print $pubkey->lastErrorText() . "\n";

    exit;
}

print 'Public key exported to all file formats.' . "\n";

?>