freeCodeCamp/curriculum/challenges/chinese/02-javascript-algorithms-and-data-structures/basic-data-structures/generate-an-array-of-all-object-keys-with-object.keys.chinese.md

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---
id: 587d7b7d367417b2b2512b1e
title: Generate an Array of All Object Keys with Object.keys()
challengeType: 1
videoUrl: ''
localeTitle: 使用Object.keys生成所有对象键的数组
---
## Description
<section id="description">我们还可以使用<code>Object.keys()</code>方法生成一个数组,其中包含存储在对象中的所有键,并传入一个对象作为参数。这将返回一个数组,其中的字符串表示对象中的每个属性。同样,数组中的条目没有特定的顺序。 </section>
## Instructions
<section id="instructions">完成编写<code>getArrayOfUsers</code>函数,以便它返回一个数组,该数组包含它作为参数接收的对象中的所有属性。 </section>
## Tests
<section id='tests'>
```yml
tests:
- text: <code>users</code>对象仅包含<code>Alan</code> <code>Jeff</code> <code>Sarah</code><code>Ryan</code>
testString: assert('Alan' in users && 'Jeff' in users && 'Sarah' in users && 'Ryan' in users && Object.keys(users).length === 4);
- text: <code>getArrayOfUsers</code>函数返回一个数组,其中包含<code>users</code>对象中的所有键
testString: assert((function() { users.Sam = {}; users.Lewis = {}; let R = getArrayOfUsers(users); return (R.indexOf('Alan') !== -1 && R.indexOf('Jeff') !== -1 && R.indexOf('Sarah') !== -1 && R.indexOf('Ryan') !== -1 && R.indexOf('Sam') !== -1 && R.indexOf('Lewis') !== -1); })() === true);
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='js-seed'>
```js
let users = {
Alan: {
age: 27,
online: false
},
Jeff: {
age: 32,
online: true
},
Sarah: {
age: 48,
online: false
},
Ryan: {
age: 19,
online: true
}
};
function getArrayOfUsers(obj) {
// change code below this line
// change code above this line
}
console.log(getArrayOfUsers(users));
```
</div>
</section>
## Solution
<section id='solution'>
```js
// solution required
```
</section>