Javascript's [defer] and [async] _ javascript tips-js tutorial

This article mainly introduces the [defer] and [async] attributes of js & lt; script & gt;. For more information, see [defer].

You can add the defer attribute to script to tell the browser that this script does not need to be executed immediately. Then, the browser will execute this script after the file is fully loaded, which is equivalent to window. onload, but it is better than window. onload is more flexible.

The Code is as follows: