Comment by gpvos

When I used PdfSharp about 9 years ago, it wasn't really designed to import arbitrary PDFs; it crashed or hung on many less common constructs or invalid PDF files. It was really only designed to either create PDFs or edit PDFs created by itself (or MigraDoc, which used it); that it could also import some other PDFs was considered a bonus by its maintainers. I submitted some patches back then to fix the most egregious problems. Hopefully it has improved.

We needed a library to read arbitrary PDF files (although I forgot what exactly we needed to read from them; it wasn't for full rendering) and ended up using PdfSharp, because iText did not respond to our pricing request.