AppendToFile, incremental updates

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   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?

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mhnejmles Members Profile Find Members Posts Beginner Joined: 10 Feb 17 Status: Offline Points: 3	Post Options Post Reply Quote mhnejmles Report Post Thanks(0) Quote Reply Topic: AppendToFile, incremental updates Posted: 10 Feb 17 at 1:55AM
	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?

Ingo Members Profile Find Members Posts Moderator Group Joined: 29 Oct 05 Status: Offline Points: 3529	Post Options Post Reply Quote Ingo Report Post Thanks(0) Quote Reply Posted: 10 Feb 17 at 8:21AM
	Hi mhnejmles, you should put your code into a try/finally structure to be more save. What's inside input_file? It should be always the same name. Please read the description regarding AppendToFile (then you'll know while corruption can appear): http://www.debenu.com/docs/pdf_library_reference/AppendToFile.php Here you can read about incremental updates: http://www.debenu.com/kb/incremental-updates/ Cheers and welcome here, Ingo
	Cheers, Ingo

mhnejmles Members Profile Find Members Posts Beginner Joined: 10 Feb 17 Status: Offline Points: 3	Post Options Post Reply Quote mhnejmles Report Post Thanks(0) Quote Reply Posted: 10 Feb 17 at 5:58PM
	Hi, thanks for the reply Sorry, was working really late last night and I didn't have the strength to write everything down here. I am working with the 13.11 Delphi version of QuickPDFLibrary in Delphi Berlin 10.1. 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

Ingo Members Profile Find Members Posts Moderator Group Joined: 29 Oct 05 Status: Offline Points: 3529	Post Options Post Reply Quote Ingo Report Post Thanks(0) Quote Reply Posted: 11 Feb 17 at 10:20PM
	if you wanna tell about an error this is the wrong place here... Try the official support pages in this case.
	Cheers, Ingo