以未提交的形式關閉頁面時要求確認

Question

我有一個表單，並且我希望在提交值之前用戶關閉頁面時要求確認。我已經嘗試了this question中描述的腳本，但它似乎不起作用：userSubmitted的值總是如此，並且彈出窗口沒有出現。

模板中的代碼是：

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

在我的控制器代碼：

$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.'); 
    } 

});