Here is a person in the same situation as me
http://topic.csdn.net/t/20020826/11/970138.html
But someone in the post tested it and there was no problem. The IE6 I tested was under Windows 2003. I don’t know if the problem has been fixed under XP.
I found an official help document from Microsoft about this BUG in IE5.
http://support.microsoft.com/kb/238004/zh-cn
The solution is to use a global variable to limit the three triggered events to only execute once, and then reset the variable after 200ms.
This problem is relatively rare, so I would like to record it