Prevent close windows with confirm

gistfile1.txt

onbeforeunload = function(e){
  if(confirm('Are you nuts? Do you really want to leave me?')){
		return 'OK, Good Bye then';
	}
	else {
		e = e || event;
		if(e.preventDefault){e.preventDefault();}
		e.returnValue = false;
		return 'I said, "Are you nuts? Do you really want to leave me?"';
	}
}