2018-10-10 18:03:03 -04:00
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---
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id: 587d7b8a367417b2b2512b4d
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challengeType: 1
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2020-08-04 15:13:35 +08:00
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forumTopicId: 301217
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localeTitle: 使用解构赋值将对象作为函数的参数传递
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2018-10-10 18:03:03 -04:00
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---
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## Description
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2020-08-04 15:13:35 +08:00
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<section id='description'>
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在某些情况下,你可以在函数的参数里直接解构对象。
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请看以下代码:
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```js
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const profileUpdate = (profileData) => {
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const { name, age, nationality, location } = profileData;
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// do something with these variables
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}
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```
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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:
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```js
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const profileUpdate = ({ name, age, nationality, location }) => {
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/* do something with these fields */
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}
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```
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这样的操作去除了多余的代码,使代码更加整洁。
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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。
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</section>
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2018-10-10 18:03:03 -04:00
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## Instructions
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2020-08-04 15:13:35 +08:00
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<section id='instructions'>
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对<code>half</code>的参数进行解构赋值,使得仅仅将<code>max</code>与<code>min</code>的值传进函数。
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</section>
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2018-10-10 18:03:03 -04:00
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## Tests
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<section id='tests'>
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```yml
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tests:
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2020-08-04 15:13:35 +08:00
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- text: <code>stats</code>的类型应该是一个<code>object</code>。
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testString: assert(typeof stats === 'object');
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- text: <code>half(stats)</code>应该等于<code>28.015</code>
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testString: assert(half(stats) === 28.015);
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- text: 应该使用解构赋值。
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testString: assert(code.replace(/\s/g, '').match(/half=\({\w+,\w+}\)/));
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- text: 应该使用解构参数。
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testString: assert(!code.match(/stats\.max|stats\.min/));
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2018-10-10 18:03:03 -04:00
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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const stats = {
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max: 56.78,
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standard_deviation: 4.34,
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median: 34.54,
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mode: 23.87,
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min: -0.75,
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average: 35.85
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};
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2020-08-04 15:13:35 +08:00
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// change code below this line
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const half = (stats) => (stats.max + stats.min) / 2.0; // use function argument destructuring
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// change code above this line
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2018-10-10 18:03:03 -04:00
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console.log(stats); // should be object
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console.log(half(stats)); // should be 28.015
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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2020-08-04 15:13:35 +08:00
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const stats = {
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max: 56.78,
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standard_deviation: 4.34,
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median: 34.54,
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mode: 23.87,
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min: -0.75,
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average: 35.85
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};
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const half = ( {max, min} ) => (max + min) / 2.0;
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2018-10-10 18:03:03 -04:00
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```
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2020-08-04 15:13:35 +08:00
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2018-10-10 18:03:03 -04:00
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</section>
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