javascript 在 Java Script 中关闭窗口之前显示警告消息
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Show warning message before close window in Java Script
提问by Coolguy
I've try this:
我试过这个：
<body onunload="LogoutNoAsk();"> </body>
and the function is:
功能是：
function LogoutNoAsk()
{
alert("Please press the Logout button to logout.");
parent.close();
}
When I press close which is the 'X' button on the top right of the window, it close straightaway without the warning message. What's wrong?
当我按下窗口右上角的“X”按钮关闭时，它会立即关闭而没有警告消息。怎么了？
回答by Aaron Powell
You're actually wanting to use the onbeforeunloadevent which allows you to block the close event.
您实际上想要使用onbeforeunload允许您阻止关闭事件的事件。
See the MDN referencefor details, but the code required would be:
有关详细信息，请参阅MDN 参考，但所需的代码是：
window.onbeforeunload = function(e) {
return 'Please press the Logout button to logout.';
};
