This was an interesting question that came in from a reader:
I need to show a warning message on unload event of window. I'm using below code.
Problem is its coming on all hyperlinks, submit buttons. and if i try to trap event object, its coming as NULL.
The code he was using made use of the beforeunload window event. Now - let me state right away I’m hate sites that do something when I try to leave them. That being said - he was trying to prevent folks from losing work when closing a window or tab by mistake. At the same time though he didn’t want his safety code to run on simple clicks (or form submits). Here’s the method I came up with. It just supports ignoring links, not form submits, but I’ll throw it out there for folks to tear apart.
</body> </html> </code>
Basically, I listen to both the click event and the beforeunload event. If a click happens (on a link), I unbind the beforeunload listener allowing the person to leave the page without getting the message. What do folks think? Ignoring the fact that it won't work on a form submit (but that's trivial enough to add), are there any other ways this can be improved?