EventEmitter 类

EventEmitter 类由 events 模块定义和暴露：

const EventEmitter = require('events');

所有的 EventEmitter，当添加新的监听器时触发事件 'newListener'，当删除现有的监听器时触发事件 'removeListener'。

它支持以下的选项：

• captureRejections <boolean> 启用自动捕获 promise 拒绝。

The EventEmitter class is defined and exposed by the events module:

const EventEmitter = require('events');

All EventEmitters emit the event 'newListener' when new listeners are added and 'removeListener' when existing listeners are removed.

It supports the following option:

• captureRejections <boolean> It enables automatic capturing of promise rejection. Default: false.