这个小例子虽然很简单，但却很实用，它完成了自动监测U盘等移动设备在插入或拨出电脑时弹出提示，当然你可能需要的不是它弹出提示，而是判断是否有设备插拨，不过稍微改一下就能满足你的需求了。-This small example is very simple, but very practical that it has completed the automatic monitoring of U disk and other mobile devices to insert or set aside