68.实现Event

[I am ne zha / Jeskson]

class EventEmiter {
 constructor() {
  this._EventPool = new Map();
 }
 on(event, callback) {
  this._EventPool.get(event) || this._EventPool.set(event, []);
  if (typeof callback === 'function') {
   this._Event.get(event).push(callback);
  } else {
    throw new Error('callback not is function')
  }
 }
 addEventListener(event, callback) {
  this.on(event, callback)
 }

 emit(event, ...args) {
  Promise.resolve().then(() => {
   let funcs = this._EventPool.get(event);
   if (funcs) {
    funcs.forEach(f => f(...args))
   } else {
    throw new Error(`${event} not register`)
   }
  })
 }
 send(event, ...args) {
  this.emit(event, ...args)
 ]
 removeListener(event) {
   Promise.resolve().then(() => {
    if (event) {
     this._EventPool.delete(event)
    } else {
     throw new Error(`${event} not register`}
    }
   })
 }
}


// 发布订阅模式，实现Event类，支持once，on，off，emit
class Event {
 listeners = {}
 
 on(type, fn) {
  if (this.listeners[type]) {
   this.listeners[type].push(fn);
  } else {
   this.listeners[type] = [fn]
  }
 }
 emit(type, ...args) {
  this.listeners[type].forEach((fn) => {
   fn.apply(this, args);
  });
 }
 off(type, fn) {
  const index = this.listeners[type].indexOf(fn);
  this.listenrs[type].splice(i, 1);
 }
 once(type, fn) {
  const cb = (...args) => {
   fn.apply(this, args);
   this.off(type, fn);
  };
  this.on(type, cb);
 }
}


// ----------------------------
const Event = function() {
 const EventPool = new Map();
 const isFunction = func => typeof func === 'function';
 const on = (event, callback) => {
  EventPool.get(event) || Event.set(event, []);
  if (isFunction(callback)) {
    EventPool.get(event).push(callback);
  } else {
    throw new Error('callback not is function')
  }
 };
 
 const addEventListener = (event, callback) => {
  on(event, callback);
 };
 
 const emit = (event, ...args) => {
  Promise.resolve().then(() => {
    let funcs = EventPool.get(event);
    if (funcs) {
      funcs.forEach(f => f(...args));
    } else {
      throw new Error(`${event} not registor')
    }
  });
 }
 
 const send = (event, ...args) => {
   emit(event, ...args)
 };
 
 const removeListener = event => {
   Promise.resolve(() => {
    if (event) {
      EventPool.delete(event);
    } else {
     throw new Error(`${event} not register`)
    }
   });
 };
 return {
  on, emit, addEventListener, send 
 }
}();