JS之路：Promise

时间：2020-12-17 11:50:39 收藏：0 阅读：28

手动实现一个简易版的Promise

function PromiseSimple (excutor) {

let _this = this

let _status = ‘pending‘

let successCallBack = undefined

let failCallBack = undefined

excutor(resolve.bind(_this), reject.bind(_this))

function resovle (params) {

if (_this._status === ‘pending‘) {

_this._status = ‘full‘

_this.successCallBack(params)

}

function reject (params) {

if (_this._status === ‘pending‘) {

_this._status = ‘fail‘

_this.failCallBack(params)

}

PromiseSimple.prototype.then = function (full, fail) {

this.successCallBack = full

this.failCallBack = fail

}

原文：https://www.cnblogs.com/fontyou/p/14148006.html