PHP Requires Chilkat v11.7.0+

Find Out Whether a PDF Needs a Password Before Loading It

See more PDF Protection Examples

Demonstrates PreLoadCheck, which examines a PDF file without loading it and without any password. It reports whether the file is encrypted, by which method and algorithm, whether a password is needed to open it, and what its permissions are. An application uses it to decide whether to ask for a password, or which certificate it needs, before calling LoadFile. PreLoadCheckBd does the same for a PDF held in memory. Chilkat2 PHP

<?php

use Chilkat2\JsonObject;
use Chilkat2\Pdf;

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

// The PDF used in this example is available at two_page_memo.pdf

// The PDF used in this example is available at encrypted_user_password.pdf

// The PDF used in this example is available at no_copy_permission.pdf

$pdf = new Pdf();
$info = new JsonObject();

// A PDF that is not encrypted.  Nothing but "encrypted" is reported for it.
try {
    $pdf->PreLoadCheck('qa_data/pdf/two_page_memo.pdf', $info);
} catch (\Chilkat2\Exception $e) {
    echo $e->getMessage(), "\n";
    exit;
}

echo "two_page_memo.pdf\n";
echo '  encrypted: ', ($info->BoolOf('encrypted') ? 'true' : 'false'), "\n";

// A PDF that needs a password to open.
try {
    $pdf->PreLoadCheck('qa_data/pdf/encrypted_user_password.pdf', $info);
} catch (\Chilkat2\Exception $e) {
    echo $e->getMessage(), "\n";
    exit;
}

echo "encrypted_user_password.pdf\n";
echo '  encrypted: ', ($info->BoolOf('encrypted') ? 'true' : 'false'), "\n";
echo '  method: ', $info->StringOf('method'), "\n";
echo '  algorithm: ', $info->StringOf('algorithm'), "\n";
echo '  openPasswordRequired: ', ($info->BoolOf('openPasswordRequired') ? 'true' : 'false'), "\n";

// A PDF that opens without a password but is restricted.  The permissions are readable without
// any password.
try {
    $pdf->PreLoadCheck('qa_data/pdf/no_copy_permission.pdf', $info);
} catch (\Chilkat2\Exception $e) {
    echo $e->getMessage(), "\n";
    exit;
}

echo "no_copy_permission.pdf\n";
echo '  encrypted: ', ($info->BoolOf('encrypted') ? 'true' : 'false'), "\n";
echo '  openPasswordRequired: ', ($info->BoolOf('openPasswordRequired') ? 'true' : 'false'), "\n";
echo '  may copy: ', ($info->BoolOf('permissions.copy') ? 'true' : 'false'), "\n";

// The typical use: ask for a password only when one is needed, then load.
try {
    $pdf->PreLoadCheck('qa_data/pdf/encrypted_user_password.pdf', $info);
} catch (\Chilkat2\Exception $e) {
    echo $e->getMessage(), "\n";
    exit;
}

if ($info->BoolOf('openPasswordRequired')) {
    // An application would prompt for the password here.
    $pdf->UserPassword = 'secret';
}

try {
    $pdf->LoadFile('qa_data/pdf/encrypted_user_password.pdf');
} catch (\Chilkat2\Exception $e) {
    echo $e->getMessage(), "\n";
    exit;
}

echo 'loaded, pages: ', $pdf->NumPages, "\n";

// Sample output:

// two_page_memo.pdf
//   encrypted: False
// encrypted_user_password.pdf
//   encrypted: True
//   method: password
//   algorithm: rc4-128
//   openPasswordRequired: True
// no_copy_permission.pdf
//   encrypted: True
//   openPasswordRequired: False
//   may copy: False
// loaded, pages: 1