Try the official support pages in this case.

I did go through the description and sample code based on the knowledge base topic about incremental updates to PDFs already.

I will elaborate more on the details....

So I basically copied the code structure from the sample. I was also trying to do some more with it but I came to the conclusion there might be a bug. So let's say I have a pdf file with a filepath. It's a simple pdf file I generated from a Word through Adobe PDF printer with some text in it. I wanna try to append some changes to the file. So I create a new form and a simple code:

unit Unit1;

interface

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

Const QPDFLicKey='licensekey';

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private

  public
    { Public declarations }
  end;

function QuickPDFLib_AppendToPDF(filepath: String): Boolean;

var
  Form1: TForm1;

implementation

{$R *.dfm}

function QuickPDFLib_AppendToPDF(filepath: String): Boolean;
var PDF: TDebenuPDFLibrary;
begin
  result:= false;
  PDF:= TDebenuPDFLibrary.Create;
  PDF.UnlockKey(QPDFLicKey);

  if PDF.LoadFromFile(filepath ,'') > 0 then
    begin
      if PDF.AppendToFile(filepath) > 0 then
        result:= true;
    end;
end;

procedure TForm1.Button1Click(Sender: TObject);
var
  res: boolean;
begin
  res:= QuickPDFLib_AppendToPDF('C:\pdf_work\test_pdf.pdf');
  if res then
    ShowMessage('Success!!')
  else
    ShowMessage('Fail!!');
end;

end.

And when I use the button, 'Success' message appears. But when I open the pdf file:

- in adobe reader, it gives me error 14, that the file is corrupted

- in google chrome, the file won't load

- tried MS Edge, the file did load there surprisingly

the code is just basic load and append nothing more when I do the same thing using Direct Access(DA) there is no problém, the pdf file saves fine. Problem is that DA doesnt have a lot of the usual functionality.

At first I tried to do some more stuff with it, like add an embedded file, merge 2 documents together and the result file came out alright when I use SaveToFile function. But whenever I use AppendToFile, the result file gets corrupted.

Note: the filepath always stays the same, so I am appending to the same file I open. If you don't give it the same file then the library throws an exception. I can upload the files somewhere if deemed neccessary. But I was kinda curious whether anyone else has encountered this.

Hope it is somewhat understandable,

mhnejmles

So, has anyone been working with incremental updates lately? I've been trying to make it work in the latest 13.11 version but to no avail. Every pdf file I append goes corrupted and is unusable in most PDF viewers.

Even such a simple code like:

var
  PDF: TDebenuPDFLibrary;
  res: Integer;
begin
  PDF:= TDebenuPDFLibrary.Create;
  PDF.UnlockKey(const_key);

  res:= PDF.LoadFromFile(input_file, '');
  res:= PDF.AppendToFile(input_file);

  PDF.Free;
end;

ends up destroying the pdf file. And no changes were made to it. Direct Access functions work fine but you have less functionality in it. So have anyone else encountered this?