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PHP Extension

Export Digital Certificate's Public Key

See more Certificates Examples

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.

Chilkat PHP Extension Downloads

PHP Extension
<?php

include("chilkat.php");

$success = false;

$cert = new CkCert();

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

// Get the public key:
$pubkey = new CkPublicKey();
$cert->GetPublicKey($pubkey);

// Save to various formats:
$success = $pubkey->SaveDerFile(false,'/Users/chilkat/testData/pubkeys/chilkat_pkcs8.der');
if ($success != true) {
    print $pubkey->lastErrorText() . "\n";
    exit;
}

$success = $pubkey->SavePemFile(false,'/Users/chilkat/testData/pubkeys/chilkat.pem');
if ($success != true) {
    print $pubkey->lastErrorText() . "\n";
    exit;
}

$success = $pubkey->SaveDerFile(true,'/Users/chilkat/testData/pubkeys/chilkat_pkcs1.der');
if ($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";

?>