Q:
I need to be able to “copy” a portion of a source pdf and save it as another PDF. So for instance say I want to grab rectangle 0,0,100,100 from the source pdf and create another pdf that is 100 x 100 and contains the original contents.
A:
One possibility is to use the ElementBuilder class (http://www.pdftron.com/pdfnet/samplecode/ElementBuilderTest.java) to iterate through a page, and write the elements inside the rectangle to the output file. You can also achieve this by making a copy of a page and run redaction on the new page. You can find more information about the redaction feature from the following links:
http://www.pdftron.com/pdfnet/samplecode/PDFRedactTest.java
http://www.pdftron.com/pdfnet/Javadoc/pdftron/PDF/Redactor.html