{"id":548,"date":"2011-06-21T08:01:00","date_gmt":"2011-06-21T15:01:00","guid":{"rendered":"http:\/\/www.quickpdflibrary.com\/blog\/?p=548"},"modified":"2011-06-21T08:01:00","modified_gmt":"2011-06-21T15:01:00","slug":"device-context-handles-and-signedunsigned-integers","status":"publish","type":"post","link":"https:\/\/www.quickpdflibrary.com\/blog\/2011\/06\/device-context-handles-and-signedunsigned-integers\/","title":{"rendered":"Device context handles and signed\/unsigned integers"},"content":{"rendered":"

For Quick PDF Library version 7.25 we changed the integer type of the device context handles returned by the GetCanvasDC<\/strong> function and accepted as parameters to the RenderPageToDC <\/strong>and DARenderPageToDC <\/strong>functions.<\/p>\n

The reason for this is that the Delphi VCL declares the HDC <\/strong>type as an unsigned 32-bit integer.<\/p>\n

The Windows graphics system does return values in the entire unsigned 32-bit range.<\/p>\n

However, since making the change in 7.25 we have done further research and found some inconsistencies in various programming environments.<\/p>\n

In particular, the Windows SDK defines a device context handle HDC <\/strong>as a PVOID <\/strong>which is a signed 32-bit integer.<\/p>\n

The .NET Framework uses System.IntPtr<\/strong> which is also a signed 32-bit integer.<\/p>\n

For 7.26 we will be making further changes to how device context handles are processed by Quick PDF Library to properly match different programming languages.<\/p>\n