class EventEmitter {constructor() {this.emitter = {}}on(eventName,cb) {if (this.emitter[eventName]) {this.emitter[eventName].push(cb)} else {this.emitter[eventName] = []this.emitter[eventName].push(cb)}}emit(eventName,...str) {if (this.emitter[eventName]) {for (let item of this.emitter[eventName]) {item(...str)}} else {throw eventName + ‘is not definde‘;}}}const eventEmitter = new EventEmitter();const connectHandler = (str,str1) => { console.log(‘连接成功1。‘+str,str1);eventEmitter.emit(‘data_received‘);}eventEmitter.on(‘connection‘, connectHandler);eventEmitter.on(‘connection‘, (str,str1) => {console.log(‘连接成功2。‘+str,str1);});eventEmitter.on(‘data_received‘, () =>{console.log(‘数据接收成功。‘)});eventEmitter.emit(‘connection‘,‘teststr‘,‘xxxxxx‘);console.log(‘程序执行完毕。‘)
nodeJs---emitter模块（模拟封装）
原文地址：https://www.cnblogs.com/kingkun/p/9038676.html