javascript confirm dialog box before close browser window

Question

I need to display a confirm dialog box before closing the browser window using javascript or PHP. The confirm box should come up when I click the close button of browser; ot

Answer 1

This will display it when closing the browser:

window.onbeforeunload = function (event) {
  var message = 'Sure you want to leave?';
  if (typeof event == 'undefined') {
    event = window.event;
  }
  if (event) {
    event.returnValue = message;
  }
  return message;
}