The PrintDocument method displays the print dialog for the
currently loaded document. The dialog is shown asynchronously and the
method will return once the print user interface has been invoked. This
method does not perform the printing operation itself; it only initiates
the print workflow and allows the user to select a printer, adjust
preferences, and confirm printing.
This method can only be called after navigation has completed and the
current document is fully loaded. If navigation is still in progress when
the method is called, it will fail with an error indicating that the
operation is in progress. This method only supports interactive printing
through a user interface. If you need to programmatically export the document
without user interaction, use the SaveDocument method instead.