A、B两个操作在需要等一个异步操作完成后操作

Question

A、B两个操作在需要等一个网络请求完成后操作，但是可能是A，也可能是B，还可能是AB或者BA，AB两个操作在不同的js文件中。
对于这种情况大家一般怎么处理的呢？谢谢了！
ps：请求在微信小程序中，无法添加async: false属性

---

先谢谢大家的回答了，我之前也是想过promise的。但是这个网络请求是在app()里面的。

这里怎么使用promise就觉得有点没有头绪。

Answer 1

简单粗暴：监听一段时间（自定义，如20秒）//两个请求是否完成的状态，在每个请求里面回填这个状态，改成1var wait = 20, result = { ajax1: 0, ajax2: 0 };var siFlag = setInterval(function () {&nbsp; &nbsp; wait--;&nbsp; &nbsp; if (wait < 1) {&nbsp; &nbsp; &nbsp; &nbsp; clearInterval(siFlag);&nbsp; &nbsp; }&nbsp; &nbsp; var isComplete = true;&nbsp; &nbsp; for (var i in result) {&nbsp; &nbsp; &nbsp; &nbsp; if (!result[i]) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; isComplete = false;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; break;&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; }&nbsp; &nbsp; console.log(wait);&nbsp; &nbsp; //都完成时&nbsp; &nbsp; if (isComplete) {&nbsp; &nbsp; &nbsp; &nbsp; console.log("isComplete TODO");&nbsp; &nbsp; }}, 1000);//直接拷贝到控制台执行，能看效果，运行的过程中，尝试改变result对象两个属性的值

Answer 2

let in=falseA（）{C（）}B（）{C（）}C（）{if（in）{&nbsp; &nbsp; return}in = true}其实我也是瞎写的

Answer 3

Promise.all 应该可以

Answer 4

用Promise并行吧，几个异步事件一起执行，一起拿到结果，最后完成那个完成了，才获取所有的异步返回值(集合)var a = function(){&nbsp; &nbsp; return new Promise(function(resolve, reject){&nbsp; &nbsp; &nbsp; &nbsp; setTimeout(function(){&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; resolve('a');&nbsp; &nbsp; &nbsp; &nbsp; },2000);&nbsp; &nbsp; })}var b = function(){&nbsp; &nbsp; return new Promise(function(resolve, reject){&nbsp; &nbsp; &nbsp; &nbsp; setTimeout(function(){&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; resolve('b');&nbsp; &nbsp; &nbsp; &nbsp; },1000);&nbsp; &nbsp; })}var c = function(){&nbsp; &nbsp; return new Promise(function(resolve, reject){&nbsp; &nbsp; &nbsp; &nbsp; setTimeout(function(){&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; resolve('c');&nbsp; &nbsp; &nbsp; &nbsp; },3000);&nbsp; &nbsp; })}Promise.all([a(),b(),c()]).then(function(val){&nbsp; &nbsp; &nbsp; &nbsp; console.log(val);})你如果是只要有请求完成就行，那么用竞速，最先完成的完成了就执行，返回最先完成的那个异步的值Promise.race([a(),b(),c()]).then(function(val){&nbsp; &nbsp; &nbsp; &nbsp; console.log(val);})