I am trying to hide some divs before the user prints this giant form, then display the divs again afterward. Thus I want to ignore the rest of the page, and only print the form itself.
Sure I could open a separate page when the user clicks the print button. The only thing is that the form is really long and it would be quite tedious to do that.
Edit: My previous question did not actually reflect what I was looking for. So I changed it to the current one.
Also thanks to all that suggested window.onbeforeprint and window.onafterprint. That was relevant to my edited question.