Encrypt a pdf file (Delphi)

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   Hello!
how to encrypt a pdf file (Delphi) please with "Quick PDF Library" ?
I tried the following code, but it does not encrypt the file:

var
  CanProceed: Boolean;
begin

CanProceed := False;
  if dlgOpen.Execute then
  begin
    ViewPrintQP := TDebenuPDFLibrary.Create;
    if ViewPrintQP.UnlockKey(edtLicenseKey.Text) = 1 then
    begin
      if ViewPrintQP.LoadFromFile(dlgOpen.FileName, '') = 1 then
      begin
        CanProceed := True;
      end else
        MessageDlg('The PDF could not be opened.', mtError, [mbOK], 0);
    end else
      MessageDlg('The license key is invalid or has expired.', mtError, [mbOK], 0);
  end;

ViewPrintQP.Encrypt(dlgOpen.FileName , '' , 'Owner' , 'User' , 1 , 1);

ViewPrintQP.SaveToFile('E:\encrypted_doc.pdf');

it saves the file but it is not encrypted and it is not protected by password.

how to solve this problem please?

Thank you.

Best regards.
Amelie

Edited by Amelie - 05 Dec 17 at 5:46PM

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Amelie Members Profile Find Members Posts Beginner Joined: 10 Nov 17 Location: France Status: Offline Points: 13	Post Options Post Reply Quote Amelie Report Post Thanks(0) Quote Reply Topic: Encrypt a pdf file (Delphi) Posted: 05 Dec 17 at 5:39PM
	Hello! how to encrypt a pdf file (Delphi) please with "Quick PDF Library" ? I tried the following code, but it does not encrypt the file: *var* *CanProceed: Boolean;* *begin* *CanProceed := False;* *if dlgOpen.Execute then* *begin* *ViewPrintQP := TDebenuPDFLibrary.Create;* *if ViewPrintQP.UnlockKey(edtLicenseKey.Text) = 1 then* *begin* *if ViewPrintQP.LoadFromFile(dlgOpen.FileName, '') = 1 then* *begin* *CanProceed := True;* *end else* *MessageDlg('The PDF could not be opened.', mtError, [mbOK], 0);* *end else* *MessageDlg('The license key is invalid or has expired.', mtError, [mbOK], 0);* *end;* *ViewPrintQP.Encrypt(dlgOpen.FileName , '' , 'Owner' , 'User' , 1 , 1);* *ViewPrintQP.SaveToFile('E:\encrypted_doc.pdf');* it saves the file but it is not encrypted and it is not protected by password. how to solve this problem please? Thank you. Best regards. Amelie Edited by Amelie - 05 Dec 17 at 5:46PM

Ingo Members Profile Find Members Posts Moderator Group Joined: 29 Oct 05 Status: Offline Points: 3524	Post Options Post Reply Quote Ingo Report Post Thanks(0) Quote Reply Posted: 05 Dec 17 at 9:31PM
	Hi Amelie, here you can read about the encrypt-function (only four parameters are available): http://www.debenu.com/docs/pdf_library_reference/Encrypt.php And here you can read about how to generate the fourth parameter: http://www.debenu.com/docs/pdf_library_reference/EncodePermissions.php Sample for Encrypt and EncodePermission: // . . . var p5, p6, p7, p8, p9, p10, p11, p12, perm : LongInt; perm := ViewPrintQP.EncodePermissions(p6, p7, p8, p10, p9, p11, p12, 0); ViewPrintQP.Encrypt('Owner' , 'User' , 1 , perm); // . . . There's no need to insert dlgOpen.FileName into the encrypt-function 'cause the file is already known with the LoadFromFile. To make it clean you should check first, if the file is already encrypted and do a decrypt. This you can do after LoadFromFile. Here's a sample: // . . . If ( ViewPrintQP.EncryptionStatus > 0 ) Then ViewPrintQP.Decrypt; // . . . Wish you more luck with the next try ;-)
	Cheers, Ingo

tfrost Members Profile Find Members Posts Senior Member Joined: 06 Sep 10 Location: UK Status: Offline Points: 437	Post Options Post Reply Quote tfrost Report Post Thanks(1) Quote Reply Posted: 05 Dec 17 at 9:32PM
	Please check again the documentation for Encrypt. The parameters for Delphi should be Owner, User, Strength, Permissions. The filename should not be there, and the final '1' should be replaced by a value returned from an earlier call to EncodePermissions. Then, check the result code from Encrypt before you save the file. If you get a 0, call LastErrorCode to get more information. Alternatively, if all you want to do is encrypt the file, you can use EncryptFile. I am sure that users here will be happy to help you if we have a bit more detail (including the library version you are using)!

Amelie Members Profile Find Members Posts Beginner Joined: 10 Nov 17 Location: France Status: Offline Points: 13	Post Options Post Reply Quote Amelie Report Post Thanks(0) Quote Reply Posted: 06 Dec 17 at 8:25AM
	Hi, Thanks for your help. It works well ! I use version 11.13. @ tfrost : thanks for your advices Have a good day Amélie