PDFsharp & MigraDoc Foundation

With version 6.1.1, PdfPage.CropBox is defined like this:



This means that if the page does not specify a CropBox (a perfectly legal situation), the code incorrectly returns [0 0 0 0] which is not the correct value. According to the PDF specification CropBox is optional and if not specified, it defaults to the value of MediaBox.

There are 3 ways to fix this:
1. Have CropBox return null if the value isn't specified. This is the most correct, but would undoubtedly break much existing code.
2. Have CropBox return MediaBox if the value isn't specified. Probably same problem as fix #1
3. Update the documentation to explain what's happening and that code can call to get the correct null value if CropBox isn't specified

The same things apply to BleedBox, ArtBox, and TrimBox.

We will think about it.
In some cases you need the actual value of CropBox, in some cases you need the effective value which is inherited from MediaBox.

_________________
Regards
Thomas Hoevel
PDFsharp Team

Yes, but what's being returned now is neither of those. Returning [0 0 0 0] is neither the actual value nor the effective value.

Also notice that the current implementation of CropBox.get does an implicit CropBox.set which is a coding mistake called "getter-setter confusion" or "implicit modification error".

Code like this is not at all rare and will cause different results in debug vs. release: