Caution:
Avoid using this event to hide or show form objects. For example, if a form filler has already digitally signed the form, using this event to hide all button objects prior to printing will impact the state of the signature.
You can use this event to change the presence of an object to prevent it from printing. For example, you can use this event to hide text or instructions intended for the form filler to use while filling the form online.
See also 

prePrint event