The window. onbeforeunload method cannot work normally in IE _ javascript skills

The following code can detect the message that the user is about to leave, whether the user clicks close, or closes in the taskbar, click back, refresh, or press F5. The cause of the event is that, due to customer feedback at work, users often order items while browsing the Web page. However, because the user opens too many windows at once, or when hitting the keyboard, press F5 incorrectly, leading to page refresh or abnormal shutdown. In this case, all operations performed on the webpage are lost, it would be nice if we could provide a prompt when the customer's information is not processed. The following code can do this no matter whether the user clicks close, or close the task bar, click back, refresh, and press the F5 key to detect the user's upcoming message.

The Code is as follows: