Node3-3基础API----event(事件触发器)

// 如果像对象享有事件能力就要集成EventEmitter 
const EventEmitter = require(‘events‘)
//集成EventEmitter类
class CustomEvent extends EventEmitter{

}
// 实例化对象
const ce = new CustomEvent()
//绑定一个事件名
ce.on(‘test‘,()=>{
    console.log(‘this is a test‘);
})

setInterval(()=>{
    ce.emit(‘test‘)
},500)

const EventEmitter = require(‘events‘)

class CustomEvent extends EventEmitter{}
const ce = new CustomEvent() 

ce.on(‘error‘,(err,time)=>{
    console.log(err);
    console.log(time);
    
});

ce.emit(‘error‘,new Error(‘oops!‘),Date.now())

const EventEmitter = require(‘events‘)
class CustomEvent extends EventEmitter{}

const ce = new CustomEvent()
ce.once(‘test‘,()=>{
    console.log(‘test event‘);
    
})
setInterval(()=>{
    ce.emit(‘test‘)
},500)

const EventEmitter = require(‘events‘)
class CustomEvent extends EventEmitter{}
function fn1(){
    console.log(‘fn1‘);
}
function fn2(){
    console.log(‘fn2‘);
}
const ce = new CustomEvent()
ce.on(‘test‘,fn1)
ce.on(‘test‘,fn2)
setInterval(()=>{
    ce.emit(‘test‘)
},500)
setTimeout(()=>{
    // ce.removeListener(‘test‘,fn2)
    // ce.removeListener(‘test‘,fn1)
    //移除所有事件名的事件
    ce.removeAllListeners(‘test‘)
},1500)