Detecting Invalid Password?

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   LoadFromFile should return "2" if the password is incorrect in QPL 7.26.  This used to be quite reliable in 7.xx and this logic was moved to QPL 8.xx where it now returns a 0 and LastErrorCode is set to 404 - InvalidPassword.
Does the PDF file have a User and Master password ?  It could also depend on the PDF file itself. If the file has a blank user password but has a master password then the file will still open correctly with QP.SetAdvancePassword('');  - It could be that the renderer is having a problem rendering the file.  Where does the Exception happen and what is the exception reporting ?

If you send me the PDF I will see if I can reproduce the Exception in QPL 8.xx.  There have been many bugs and enhancements added to QPL 8.xx compared to 7.26.

Andrew.

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AndrewC Members Profile Find Members Posts Moderator Group Joined: 08 Dec 10 Location: Geelong, Aust Status: Offline Points: 841	Post Options Post Reply Quote AndrewC Report Post Thanks(0) Quote Reply Topic: Detecting Invalid Password? Posted: 23 Jul 12 at 7:54AM
	LoadFromFile should return "2" if the password is incorrect in QPL 7.26. This used to be quite reliable in 7.xx and this logic was moved to QPL 8.xx where it now returns a 0 and LastErrorCode is set to 404 - InvalidPassword. Does the PDF file have a User and Master password ? It could also depend on the PDF file itself. If the file has a blank user password but has a master password then the file will still open correctly with QP.SetAdvancePassword(''); - It could be that the renderer is having a problem rendering the file. Where does the Exception happen and what is the exception reporting ? If you send me the PDF I will see if I can reproduce the Exception in QPL 8.xx. There have been many bugs and enhancements added to QPL 8.xx compared to 7.26. Andrew.

ExchangeViews Members Profile Find Members Posts Team Player Joined: 13 Mar 12 Status: Offline Points: 38	Post Options Post Reply Quote ExchangeViews Report Post Thanks(0) Quote Reply Posted: 21 Jul 12 at 8:11AM
	V8.x does not use SetAdvancePassword(). You need to directly use loadfromfile('test.pdf', password); Upgraded version return correct value for invalid password. You can try the trial version.

Wheeley Members Profile Find Members Posts Senior Member Joined: 30 Oct 05 Location: United States Status: Offline Points: 146	Post Options Post Reply Quote Wheeley Report Post Thanks(0) Quote Reply Posted: 20 Jul 12 at 8:39PM
	Straight from the upgrade to 8 technical guide: The LoadFrom* functions now return 1 on success and 0 on failure. In QPL v7 these functions would return 2 if an encrypted document made use of object streams or cross reference streams. This is no longer necessary as these functions have a new password parameter. If the wrong password is given, the LoadFrom* functions will return 0 and the LastErrorCode function will return error code 404. Wheeley

waynefulcher Members Profile Find Members Posts Senior Member Joined: 23 Jun 08 Location: United States Status: Offline Points: 99	Post Options Post Reply Quote waynefulcher Report Post Thanks(0) Quote Reply Posted: 20 Jul 12 at 1:53PM
	I have no problem upgrading but are you saying 8.x will work differently than 7.26 as far as what I described? Can you tell me what will be different in 8.x that would allow me to have a controlled test to see if the password is invalid? Does RenderPageToStream() return somethig different? Does LoadFromFile() return something different?

ExchangeViews Members Profile Find Members Posts Team Player Joined: 13 Mar 12 Status: Offline Points: 38	Post Options Post Reply Quote ExchangeViews Report Post Thanks(0) Quote Reply Posted: 20 Jul 12 at 8:54AM
	Use QuickPDF 8.xx.

waynefulcher Members Profile Find Members Posts Senior Member Joined: 23 Jun 08 Location: United States Status: Offline Points: 99	Post Options Post Reply Quote waynefulcher Report Post Thanks(0) Quote Reply Posted: 18 Jul 12 at 4:01PM
	I am using Delphi 7 and QuickPDF 7.26. I have a program that allows the user to select a PDF file from disk and it gives them the option to input a password in case the PDF is secured. My program then calls SetAdvancePassword(), then LoadFromFile(). Then it loops for each page calling RenderPageToStream(). I then display the rendered image so the user can view each page. All of this code works fine if...The PDF is not secured or the PDF is secured and the user has supplied the correct password. But if the PDF is secured and the user supplies an incorrect password, I can't seem to figure out how to "detect" that. The LoadFromFile() method works and returns a 1. The RenderPageToStream() also returns a 1 and the LastRenderError is blank. So I have no way to detect it actually fails. The result is the rendered image is just a blank white image. The odd thing is when I run my program from the Delphi IDE, the call to RenderPageToStream() actually throws an exception message that shows up in the Delphi IDE but the QuickPDF library must be trapping that exception because I do not get an exception in my code. So once again I cant seem to figure out how to detect an invalid password. Any help would be much appriciated. Wayne