使用未提交的表单关闭页面时询问确认

Question

我有一个表单,在提交值之前,我想询问用户关闭页面的确认.我已经尝试过这个问题中描述的脚本, 但它似乎不起作用:userSubmitted值数字总是如此,并且弹出窗口没有出现.

我的模板中的代码是:

 <script>
window.onbeforeunload = function() {
if(!userSubmitted)
    return 'Are you sure that you want to leave this page?';};
</script>

我的控制器中的代码是:

$userSubmitted=false;
//...

$form->handleRequest($request);
       if ($form->isValid()) {
        $userSubmitted=true;

//...
return $this->render('DefaultBundle::formupload.html.twig', array(
       'form' => $form->createView(), 'userSubmitted->$userSubmitted
       )); 
//...

Answer 1

var warn_on_unload = false; //default false 


$('input,textarea,select').on('change', function () { 
  //making true when user types in , or select
    warn_on_unload = true;
});

$(window).bind('beforeunload', function(){
//warns user if not saving form and closing or browsing other page
    if(warn_on_unload)
    {
        return confirm('Leaving this page will cause any unsaved data to be lost.');
    }

});