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

id, challengeType, forumTopicId, localeTitle

id	challengeType	forumTopicId	localeTitle
587d7b89367417b2b2512b49	1	301215	使用解构赋值从对象中分配变量

Description

可以在解构的属性后添加冒号和新的变量名来给解构的值赋予一个新的变量名。

还是以上个例子的对象来举例：

const user = { name: 'John Doe', age: 34 };

这是指定新的变量名的例子：

const { name: userName, age: userAge } = user;
// userName = 'John Doe', userAge = 34

获取到了 user.name 的值并赋值给名为 userName 的变量。

Instructions

使用解构赋值语句替换两个赋值语句。确保 HIGH_TEMPERATURES 的 today 和 tomorrow 属性赋值给 highToday 和 highTomorrow。

Tests

tests:
  - text: 应该移除 ES5 赋值语句。
    testString: assert(!code.match(/highToday = HIGH_TEMPERATURES\.today/g) && !code.match(/highTomorrow = HIGH_TEMPERATURES\.tomorrow/g))
  - text: 应该使用解构赋值语句创建  <code>highToday</code> 变量。
    testString: assert(code.match(/(var|const|let)\s*{\s*(today:\s*highToday[^}]*|[^,]*,\s*today\s*:\s*highToday\s*)}\s*=\s*HIGH_TEMPERATURES(;|\s+|\/\/)/g));
  - text: 应该使用解构赋值语句创建  <code>highTomorrow</code> 变量。
    testString: assert(code.match(/(var|const|let)\s*{\s*(tomorrow:\s*highTomorrow[^}]*|[^,]*,\s*tomorrow\s*:\s*highTomorrow\s*)}\s*=\s*HIGH_TEMPERATURES(;|\s+|\/\/)/g));

Challenge Seed

const HIGH_TEMPERATURES = {
  yesterday: 75,
  today: 77,
  tomorrow: 80
};

// change code below this line
  
const highToday = HIGH_TEMPERATURES.today;
const highTomorrow = HIGH_TEMPERATURES.tomorrow; 

// change code above this line

console.log(yesterday) // should be not defined
console.log(highToday); // should be 77
console.log(highTomorrow); // should be 80

Solution

const HIGH_TEMPERATURES = {
  yesterday: 75,
  today: 77,
  tomorrow: 80
};

// change code below this line
  
const { today: highToday, tomorrow: highTomorrow } = HIGH_TEMPERATURES;

// change code above this line

console.log(highToday); // should be 77
console.log(highTomorrow); // should be 80