How to use javascript event delegation and its advantages

This article mainly introduces the usage and benefits of javascript event delegation. If you are interested, refer to this article to briefly introduce the usage and benefits of javascript event delegation, for your reference, the specific content is as follows:

Event delegation: add the event to the parent level based on the principle of bubbling to trigger the execution effect,
Benefit: improves performance. The newly added elements also have previous events.
Event object: event source. No matter which event, the element you operate on is the event source.

Get event Source:
IE: Window. event. srcElement

Standard: Event.tar get target. nodeName to determine which tag is used

The code application is as follows: