(Delphi ActiveX) Certify a PDF and Lock the Entire Document

See more PDF Signatures Examples

This example demonstrates how to a sign a certify a PDF and lock the entire document. Normally this is intended to seal the document with a final approving (or dissapproving) signature; usually after a review workflow is completed and normally reserved for the creator or author of a document.

Chilkat for Delphi Downloads Chilkat ActiveX DLL for Delphi Chilkat non-ActiveX DLL for Delphi * The examples here use the ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_TLB;

...

procedure TForm1.Button1Click(Sender: TObject);
var
pdf: TChilkatPdf;
success: Integer;
json: TChilkatJsonObject;
cert: TChilkatCert;

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

pdf := TChilkatPdf.Create(Self);

// Load a PDF to be certified and locked.
// The "hello.pdf" is available at https://chilkatsoft.com/hello.pdf
success := pdf.LoadFile('qa_data/pdf/hello.pdf');
if (success = 0) then
  begin
    Memo1.Lines.Add(pdf.LastErrorText);
    Exit;
  end;

// Options for signing are specified in JSON.
json := TChilkatJsonObject.Create(Self);

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

// The only coding difference with certifying and locking a PDF
// as compared with an approval signature (also known as recipient signature)
// is to add the "lockAfterSigning" and "docMDP.add" to the json.
json.UpdateBool('lockAfterSigning',1);
json.UpdateBool('docMDP.add',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.)
cert := TChilkatCert.Create(Self);
success := cert.LoadPfxFile('qa_data/pfx/myPdfSigningCert.pfx','secret');
if (success = 0) then
  begin
    Memo1.Lines.Add(cert.LastErrorText);
    Exit;
  end;

// Tell the pdf object to use the certificate for signing.
success := pdf.SetSigningCert(cert.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(pdf.LastErrorText);
    Exit;
  end;

success := pdf.SignPdf(json.ControlInterface,'qa_output/hello_signed.pdf');
if (success = 0) then
  begin
    Memo1.Lines.Add(pdf.LastErrorText);
    Exit;
  end;

Memo1.Lines.Add('The PDF has been successfully certified and locked.');
end;