Measure the test taker's understanding about DOM Event _ javascript in javascript.

This article mainly helps you understand DOM events in javascript, solve the compatibility of DOM events, bubble DOM events, and reuse of DOM events. If you are interested, refer to the following, this article does not discuss tedious details. However, considering the reader's mental feelings and positive attitude, examples are provided here.

The title is to understand DOM events, so here we will take a simple click event as an example. We hope you can see this example before accessing the class.
At first, we implemented click on the page, just like the following simple operation.
First define a block such

Micro-universe

, And then