How to determine the PDF version of a document ?

Q: We are using PDFTron PDFNet SDK in a .NET application to check the PDF version of documents and we have found several documents for which the PDF version found by our application is different from the PDF version given by Adobe Acrobat: our application indicates a PDF Version 1.4 while Acrobat indicates a PDF Version 1.5 in the document properties.

Most of the concerned documents have been produced by Adobe Acrobat or Adobe Distiller 9 or 10.

In our code, we try to get the PDF version by two different ways (doc is a PDFDoc object representing our document):

  • By checking the header: doc. GetHeader();

  • By checking the document catalog : doc.GetRoot().FindObj(“Version”);

Could you give us more information on how to get the same PDF version information through PDFNet than through the document properties in Adobe Acrobat?