mirror of
https://github.com/qianguyihao/Web.git
synced 2024-11-01 13:34:46 +08:00
28 lines
440 B
Markdown
28 lines
440 B
Markdown
|
## 这些代码的打印结果是什么？
|
|||
|
|
|
|||
|
|
想要考察一个人对 Promise 的掌握程度，就让他看看这些代码的打印结果是什么。
|
|||
|
|
|
|||
|
|
**例1**：resolve()多次
|
|||
|
|
|
|||
|
|
```js
|
|||
|
|
const promise = new Promise((resolve, reject) => {
|
|||
|
|
resolve();
|
|||
|
|
resolve();
|
|||
|
|
});
|
|||
|
|
|
|||
|
|
promise
|
|||
|
|
.then(res => {
|
|||
|
|
console.log('成功的回调');
|
|||
|
|
})
|
|||
|
|
.catch(err => {
|
|||
|
|
console.log('失败的回调');
|
|||
|
|
});
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
打印结果：
|
|||
|
|
|
|||
|
|
```
|
|||
|
|
成功的回调
|
|||
|
|
```
|
|||
|
|
|