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freeCodeCamp/curriculum/challenges/chinese-traditional/02-javascript-algorithms-and-data-structures/es6/use-destructuring-assignment-to-assign-variables-from-objects.md

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---
id: 587d7b89367417b2b2512b49
title: 使用解構賦值從對象中分配變量
challengeType: 1
forumTopicId: 301215
dashedName: use-destructuring-assignment-to-assign-variables-from-objects
---
# --description--
可以給解構的值賦予一個新的變量名, 通過在賦值的時候將新的變量名放在冒號後面來實現。
還是以上個例子的對象來舉例:
```js
const user = { name: 'John Doe', age: 34 };
```
這是指定新的變量名的例子:
```js
const { name: userName, age: userAge } = user;
```
你可以這麼理解這段代碼:獲取 `user.name` 的值,將它賦給一個新的變量 `userName`,等等。 `userName` 的值將是字符串 `John Doe``userAge` 的值將是數字 `34`
# --instructions--
使用解構賦值語句替換兩個賦值語句。 將 `HIGH_TEMPERATURES``today``tomorrow` 的值賦值給 `highToday``highTomorrow`
# --hints--
應該移除 ES5 賦值語句。
```js
assert(
!code.match(/highToday = HIGH_TEMPERATURES\.today/g) &&
!code.match(/highTomorrow = HIGH_TEMPERATURES\.tomorrow/g)
);
```
應該使用解構賦值語句創建 `highToday` 變量。
```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
)
);
```
應該使用解構賦值語句創建 `highTomorrow` 變量。
```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` 應該等於 `77``highTomorrow` 應該等於 `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;
```