freeCodeCamp/curriculum/challenges/chinese/02-javascript-algorithms-an.../es6/use-destructuring-assignmen...

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---
id: 587d7b89367417b2b2512b49
title: 使用解构赋值从对象中分配变量
challengeType: 1
forumTopicId: 301215
dashedName: use-destructuring-assignment-to-assign-variables-from-objects
---
# --description--
可以给解构的值赋予一个新的变量名, 通过在赋值的时候将新的变量名放在冒号后面来实现。
还是以上个例子的对象来举例:
```js
const user = { name: 'John Doe', age: 34 };
```
这是指定新的变量名的例子:
```js
const { name: userName, age: userAge } = user;
```
你可以这么理解这段代码:获取 `user.name` 的值,将它赋给一个新的变量 `userName`,等等。 `userName` 的值将是字符串 `John Doe``userAge` 的值将是数字 `34`
# --instructions--
使用解构赋值语句替换两个赋值语句。 将 `HIGH_TEMPERATURES``today``tomorrow` 的值赋值给 `highToday``highTomorrow`
# --hints--
应该移除 ES5 赋值语句。
```js
assert(
!code.match(/highToday = HIGH_TEMPERATURES\.today/g) &&
!code.match(/highTomorrow = HIGH_TEMPERATURES\.tomorrow/g)
);
```
应该使用解构赋值语句创建 `highToday` 变量。
```js
assert(
code.match(
/(var|const|let)\s*{\s*(today\s*:\s*highToday[^}]*|[^,]*,\s*today\s*:\s*highToday\s*)}\s*=\s*HIGH_TEMPERATURES(;|\s+|\/\/)/g
)
);
```
应该使用解构赋值语句创建 `highTomorrow` 变量。
```js
assert(
code.match(
/(var|const|let)\s*{\s*(tomorrow\s*:\s*highTomorrow[^}]*|[^,]*,\s*tomorrow\s*:\s*highTomorrow\s*)}\s*=\s*HIGH_TEMPERATURES(;|\s+|\/\/)/g
)
);
```
`highToday` 应该等于 `77``highTomorrow` 应该等于 `80`
```js
assert(highToday === 77 && highTomorrow === 80);
```
# --seed--
## --seed-contents--
```js
const HIGH_TEMPERATURES = {
yesterday: 75,
today: 77,
tomorrow: 80
};
// Only change code below this line
const highToday = HIGH_TEMPERATURES.today;
const highTomorrow = HIGH_TEMPERATURES.tomorrow;
// Only change code above this line
```
# --solutions--
```js
const HIGH_TEMPERATURES = {
yesterday: 75,
today: 77,
tomorrow: 80
};
const { today: highToday, tomorrow: highTomorrow } = HIGH_TEMPERATURES;
```