--- id: 587d7b8a367417b2b2512b4d title: Use Destructuring Assignment to Pass an Object as a Function's Parameters challengeType: 1 forumTopicId: 301217 localeTitle: 使用解构赋值将对象作为函数的参数传递 --- ## Description
在某些情况下,你可以在函数的参数里直接解构对象。 请看以下代码: ```js const profileUpdate = (profileData) => { const { name, age, nationality, location } = profileData; // do something with these variables } ``` 上面的操作解构了传给函数的对象。这样的操作也可以直接在参数里完成: ```js const profileUpdate = ({ name, age, nationality, location }) => { /* do something with these fields */ } ``` 这样的操作去除了多余的代码,使代码更加整洁。 这样做还有个额外的好处:函数不需要再去操作整个对象,而仅仅是操作复制到函数作用域内部的参数。
## Instructions
half的参数进行解构赋值,使得仅仅将maxmin的值传进函数。
## Tests
```yml tests: - text: stats的类型应该是一个object。 testString: assert(typeof stats === 'object'); - text: half(stats)应该等于28.015 testString: assert(half(stats) === 28.015); - text: 应该使用解构赋值。 testString: assert(code.replace(/\s/g, '').match(/half=\({\w+,\w+}\)/)); - text: 应该使用解构参数。 testString: assert(!code.match(/stats\.max|stats\.min/)); ```
## Challenge Seed
```js const stats = { max: 56.78, standard_deviation: 4.34, median: 34.54, mode: 23.87, min: -0.75, average: 35.85 }; // change code below this line const half = (stats) => (stats.max + stats.min) / 2.0; // use function argument destructuring // change code above this line console.log(stats); // should be object console.log(half(stats)); // should be 28.015 ```
## Solution
```js const stats = { max: 56.78, standard_deviation: 4.34, median: 34.54, mode: 23.87, min: -0.75, average: 35.85 }; const half = ( {max, min} ) => (max + min) / 2.0; ```