window.onbeforeunload detect if POST or GET

Question

In the window.onbeforeunload event is there a way to detect if the new request is a POST (on the same page) or a GET (going to a page)? It would also be great to see the new document.location.

window.onbeforeunload = winClose;
function winClose() {
    //Need a way to detect if it is a POST or GET
    if (needToConfirm) {       
        return "You have made changes. Are you sure you want?";
    }
}

Answer 1

This is how I just did it:

$(document).ready(function(){
  var action_is_post = false;
  $("form").submit(function () {
    action_is_post = true;
  });

  window.onbeforeunload = confirmExit;
  function confirmExit()
  {
    if (!action_is_post)
      return 'You are trying to leave this page without saving the data back to the server.';
  }
});