Jquery 是否可以在 beforeunload 弹出窗口中显示自定义消息

tl;dr - You can't set custom message anymore in most modern browsers

A quick note (since this is an old answer) - these days all major browsers don't support custom message in the beforeunload popup. There is no new way to do this. In case you still do need to support old browsers - you can find the information below.

In order to set a confirmation message before the user is closing the window you can use

jQuery

$(window).bind("beforeunload",function(event) {
    return "You have some unsaved changes";
});

Javascript

window.onbeforeunload = function() {
    return "Leaving this page will reset the wizard";
};

      It's important to notice that you can't put confirm/alert inside beforeunload

还有几点注意:

1. NOT all browsers support this (more info in the Browser compatibility section on MDN) 2. In Firefox you MUST do some real interaction with the page in order for this message to appear to the user.
   3. Each browser can add his own text to your message.

Here are the results using the browsers I have access to:

Chrome:

Firefox:

Safari:

IE:

只是为了确保-您需要包含jQuery

有关浏览器支持和删除自定义消息的更多信息:

1. Chrome removed support for custom message in ver 51
2. Opera removed支持38版中的自定义消息
3. Firefox removed support for custom message in ver 44.0 (still looking for source for this information)
4. Safari removed支持9.1版中的自定义消息