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PHP

Export a Public Key as DER into a BinData

Demonstrates the Chilkat PublicKey.GetDerBd method, which writes the public key as binary DER into a BinData. The first argument selects the representation (as for GetPem) and the second is the BinData that receives the bytes (its contents are replaced).

Note: The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: The in-memory binary export: the raw DER lands in a BinData ready to hash, transmit, or hand to another API without a temporary file. It is the BinData counterpart to the text exporters, and the first argument picks the same PKCS #1 versus SubjectPublicKeyInfo structure.

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Chilkat2 PHP
<?php

use Chilkat2\BinData;
use Chilkat2\PublicKey;

// Load a public key to export.  LoadFromFile inspects the content, so it accepts DER, PEM, XML,
// JWK, and other supported representations.
$pubKey = new PublicKey();
try {
    $pubKey->LoadFromFile('qa_data/public.pem');

    // Write the public key as binary DER into a BinData.  The 1st argument selects the representation
    // (as for GetPem) and the 2nd is the BinData that receives the bytes (its contents are replaced).
    $preferPkcs1 = false;
    $bd = new BinData();
    $pubKey->GetDerBd($preferPkcs1, $bd);
} catch (\Chilkat2\Exception $e) {
    echo $e->getMessage(), "\n";
    exit;
}

echo 'Exported ', $bd->NumBytes, " DER bytes.\n";