关键在于创建Promise对象的时候，需要对外暴露两个参数。示例代码如下
| var hook = { | |
| resolve() {}, | |
| reject() {}, | |
| } | |
| var myPromise = new Promise((res, rej) => { | |
| hook.resolve = res; | |
| hook.reject = rej; | |
| }) | |
| myPromise.then(res => { | |
| console.log('Resolved:', res); | |
| }).catch(err => { | |
| console.log('Rejected:', err); | |
| }) |
之后简单了，只需调用hook.resolve()或者hook.reject()就可以任意更改 promise 对象的状态