Debenu Quick PDF Library - PDF SDK Community Forum : GetCanvasDc Cleanup

Debenu Quick PDF Library - PDF SDK Community Forum : GetCanvasDc Cleanup http://www.quickpdf.org/forum/ Copyright (c) 2006-2013 Web Wiz Forums - All Rights Reserved. Sat, 04 Apr 2026 20:29:44 +0000 Thu, 08 Dec 2011 15:16:06 +0000 http://blogs.law.harvard.edu/tech/rss Web Wiz Forums 11.01 360 www.quickpdf.org/forum/RSS_post_feed.asp?TID=1999 <![CDATA[Debenu Quick PDF Library - PDF SDK Community Forum]]> http://www.quickpdf.org/forum/forum_images/QPDF_Forum_Title.png http://www.quickpdf.org/forum/ <![CDATA[GetCanvasDc Cleanup : Great, thanks for the information...]]> http://www.quickpdf.org/forum/getcanvasdc-cleanup_topic1999_post8801.html#8801 Author: jpbro
Subject: 1999
Posted: 08 Dec 11 at 3:16PM

Great, thanks for the information Andrew.]]> Thu, 08 Dec 2011 15:16:06 +0000 http://www.quickpdf.org/forum/getcanvasdc-cleanup_topic1999_post8801.html#8801 <![CDATA[GetCanvasDc Cleanup : As stated earlier these two calls...]]> http://www.quickpdf.org/forum/getcanvasdc-cleanup_topic1999_post8796.html#8796 Author: AndrewC
Subject: 1999
Posted: 08 Dec 11 at 1:10AM

As stated earlier these two calls need to be paired. ie. Call one then the other and then the resources should be freed automatically.

If you only call CapturePage then there may be some memory that is not freed until the program is closed.

Andrew.

]]> Thu, 08 Dec 2011 01:10:59 +0000 http://www.quickpdf.org/forum/getcanvasdc-cleanup_topic1999_post8796.html#8796 <![CDATA[GetCanvasDc Cleanup : Hi Andrew - any chance you could...]]> http://www.quickpdf.org/forum/getcanvasdc-cleanup_topic1999_post8762.html#8762 Author: jpbro
Subject: 1999
Posted: 30 Nov 11 at 2:02PM

Hi Andrew - any chance you could get back to me on this? Is there any cleanup required after calling CapturePage, or does calling DrawCapturedPage release the capture page handle?]]> Wed, 30 Nov 2011 14:02:03 +0000 http://www.quickpdf.org/forum/getcanvasdc-cleanup_topic1999_post8762.html#8762 <![CDATA[GetCanvasDc Cleanup : What about after calling CapturePage?...]]> http://www.quickpdf.org/forum/getcanvasdc-cleanup_topic1999_post8662.html#8662 Author: jpbro
Subject: 1999
Posted: 09 Nov 11 at 11:42PM

What about after calling CapturePage? Do we need to cleanup by calling anything? The document doesn't say, but I'm trying to track some memory leaks in my software, so I'm investigating every possibility (BTW, I'm using QPDF 7.26)

Thanks for any advice.
]]> Wed, 09 Nov 2011 23:42:20 +0000 http://www.quickpdf.org/forum/getcanvasdc-cleanup_topic1999_post8662.html#8662 <![CDATA[GetCanvasDc Cleanup : Thanks a lot Andrew, I will make...]]> http://www.quickpdf.org/forum/getcanvasdc-cleanup_topic1999_post8517.html#8517 Author: jpbro
Subject: 1999
Posted: 17 Oct 11 at 10:07PM

Thanks a lot Andrew, I will make sure that LoadFromCanvasDC is called in my Class_Terminate event if I've previously called GetCanvasDC to ensure proper cleanup.
]]> Mon, 17 Oct 2011 22:07:31 +0000 http://www.quickpdf.org/forum/getcanvasdc-cleanup_topic1999_post8517.html#8517 <![CDATA[GetCanvasDc Cleanup : Looking at the QPL source code...]]> http://www.quickpdf.org/forum/getcanvasdc-cleanup_topic1999_post8516.html#8516 Author: AndrewC
Subject: 1999
Posted: 17 Oct 11 at 3:09PM

Looking at the QPL source code I see that a TMetaFile is actually created with the GetCanvasDC function and the DC from the Metafile is the return value. This TMetafile class is only released when LoadFromCanvasDC is called which then releases the DC.

It looks like these two calls must me called in pairs, GetCanvasDC to create the MetaFile and then cleanly release it when finished.

]]> Mon, 17 Oct 2011 15:09:25 +0000 http://www.quickpdf.org/forum/getcanvasdc-cleanup_topic1999_post8516.html#8516 <![CDATA[GetCanvasDc Cleanup : After getting a DC handle with...]]> http://www.quickpdf.org/forum/getcanvasdc-cleanup_topic1999_post8501.html#8501 Author: jpbro
Subject: 1999
Posted: 14 Oct 11 at 10:13PM

After getting a DC handle with GetCanvasDC, do we have to call DeleteDC to cleanup, or does LoadFromCanvasDC handle cleanup? What if we call GetCanvasDc but for some reason, we do not subsequently call LoadFromCavasDc - would we have to call DeleteDC then? This is for Qpdf 7.26.

Thanks for any clarifications.
]]> Fri, 14 Oct 2011 22:13:44 +0000 http://www.quickpdf.org/forum/getcanvasdc-cleanup_topic1999_post8501.html#8501