(PHP ActiveX) Sign a PDF (Simplest Possible Example)

See more PDF Signatures Examples

This example demonstrates how to a sign a PDF using mostly default options in the simplest way possible.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows Note: The php_com_dotnet.dll may need to be enabled inside of php.ini.

<?php

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

// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.Pdf')
$pdf = new COM("Chilkat.Pdf");

// Load a PDF to be signed.
// The "hello.pdf" is available at https://chilkatsoft.com/hello.pdf
$success = $pdf->LoadFile('qa_data/pdf/hello.pdf');
if ($success == 0) {
    print $pdf->LastErrorText . "\n";
    exit;
}

// Options for signing are specified in JSON.
// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.JsonObject')
$json = new COM("Chilkat.JsonObject");

// In most cases, the signingCertificateV2 and signingTime attributes are required.
$json->UpdateInt('signingCertificateV2',1);
$json->UpdateInt('signingTime',1);

// Put the signature on page 1, top left
$json->UpdateInt('page',1);
$json->UpdateString('appearance.y','top');
$json->UpdateString('appearance.x','left');

// Use a font scale of 10.0
$json->UpdateString('appearance.fontScale','10.0');

// In this example, the appearance of the digital signature will contain three lines:
// 1) The signing certificate's common name
// 2) The current date/time
// 3) Some arbitrary text.
// The keyword "cert_cn" is replaced with the Certificate's Subject Common Name.
// The keyword "current_dt" is replaced with the current date/time.
// Any number of appearance text lines can be added.
$json->UpdateString('appearance.text[0]','Digitally signed by: cert_cn');
$json->UpdateString('appearance.text[1]','current_dt');
$json->UpdateString('appearance.text[2]','The crazy brown fox jumps over the lazy dog.');

// Load the signing certificate. (Use your own certificate.)
// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.Cert')
$cert = new COM("Chilkat.Cert");
$success = $cert->LoadPfxFile('qa_data/pfx/myPdfSigningCert.pfx','secret');
if ($success == 0) {
    print $cert->LastErrorText . "\n";
    exit;
}

// Tell the pdf object to use the certificate for signing.
$success = $pdf->SetSigningCert($cert);
if ($success == 0) {
    print $pdf->LastErrorText . "\n";
    exit;
}

$success = $pdf->SignPdf($json,'qa_output/hello_signed.pdf');
if ($success == 0) {
    print $pdf->LastErrorText . "\n";
    exit;
}

print 'The PDF has been successfully cryptographically signed.' . "\n";

// The appearance of the signature appears in Adobe Acrobat as shown here:



?>