Not sure what you mean. If you want your own "Print" button to affect the document, just add more script to the button's event.
If you want to detect the moment when a user confirms the operating system print dialog (by pressing Print on that dialog), use the willPrint document event - but at that moment the spooled data is locked and changes to the document won't affect what comes out on paper, nor can you cancel the job.
I would like to know if there is some way to have some control in a html page about print statuses of a dynamically created pdf file. Here the document is loaded in an iframe. Maybe another way of working is needed?