How do I get a PDF version number from existing PDF document (similar to "PDDocGetVersion")?

Q: We are interesting in PDFTron pdf solution, would you pls check for
us if any PDFTron Product(s) to support "PDDocGetVersion" API Call ?
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A: Using PDFTron PDFNet SDK (http://www.pdftron.com/pdfnet/) you can
obtain the versioning information from the existing PDF documents. For
more information please see:

How to get PDF documents version? :

http://groups.google.com/group/pdfnet-sdk/t/21ac175902d91ff2/
http://groups.google.com/group/pdfnet-sdk/t/3c18ec257d9b9b24/
http://groups.google.com/group/pdfnet-sdk/t/e39fddedcfacf04/

How do i change the pdf version of an existing pdf document? :

http://groups.google.com/group/pdfnet-sdk/t/7ae512305cbeb97a/