[JS event -- event flow]

js event – Flow of events

Today we mainly introduce the event flow of the browser we used .

DOM2 The event flow defined by level event includes three stages ：

1. Event capture phase
2. At the target stage
3. Event bubbling stage

One 、 The previous two kinds of event flow analysis

1. Bubbling event flow
Personal understanding is similar to bubble sorting principle , That is, the event has the most specific reception , Then it bubbles upward gradually , To the page .（ That is, from the child element to the parent element ）

With the button button For example

2. Capture event flow

It is completely opposite to the principle of bubbling event flow , Events are received from page elements , Step down to the most specific elements .

The same to button Button as an example ：

Two 、JS Flow of events

JS The schematic diagram of the event is as follows ：