Confirm Dialog when i close the browser?

Question

i need to display confirm dialog box before close browser window using javascript or PHP. the confirm box should come when i click the close button of browser. other wise do

Answer 1

onunload is not very useful (in my opinion) as you can't do anything with the confirmation you're requesting (except maybe attempt to new another window with window.open, so onbeforeunload is more useful for this case.

Your better bet is onbeforeunload, which is great but won't work in Opera (though this usually isn't a deal breaker).

Like ivy said, it would look something like this: