实现一个简陋地Promise

简单实现地代码如下

class PromiseTest{
  constructor(callBack){
    this.successEventBus = [];
    this.value = null;
    this.failedEventBus = [];
    const reslove = (successData) => {
      this.value = successData;
      this.successEventBus.forEach( cb => cb(this.value))
    }
    const reject = (failedData) => {
      this.value = failedData;
      this.failedEventBus.forEach( cb => cb(this.value))
    }
    callBack(reslove, reject)  
  }
  then(cb){
    this.successEventBus.push(cb)
  }
  catch(cb){
    this.failedEventBus.push(cb)
  }

}

使用如下

let cc = new PromiseTest((reslove, reject) => {
  setTimeout(()=>{
    reslove(1)
  },10000)

})
cc.then(res => {
  console.log(res, '+++')
})