onbeforeunload不能在卸載內工作

Question

我已經寫了下面的代碼在卸載中運行onbeforeunload。但是，這似乎並不奏效。有沒有人知道我的代碼有什麼問題，無論如何，使它的工作？

$(window).unload(function() { 
    if ($('.submitAction').val() == "" && isChange) { 
     window.onbeforeunload = confirmExit; 
    } 
}); 

function confirmExit() { 
    return "If you have made any changes to the fields without clicking the Save button, your changes will be lost. Are you sure you want to exit this page?"; 
} 

Answer 1

的onunload事件是absolute last event當用戶導航離開頁面或關閉瀏覽器觸發。

結合onbeforeunload事件內的onunload事件是毫無意義的，因爲這事件已經發生（因此得名onbeforeunload）。該解決方案將綁定到onbeforeunload事件，然後事件實際發生，例如加載頁面時。

像這樣（未經）：

$(window).bind('beforeunload', function() { 
    if ($('.submitAction').val() == "" && isChange) { 
     return "If you have made any changes to the fields without clicking the Save button, your changes will be lost. Are you sure you want to exit this page?"; 
    } 
}); 

Answer 2

此行返回一個字符串：

return "If you have made any changes to the fields without clicking the Save button, your changes will be lost. Are you sure you want to exit this page?"; 

我想你的意思是：

return window.confirm("If you have made any changes to the fields without clicking the Save button, your changes will be lost. Are you sure you want to exit this page?");