42 lines
765 B
Markdown
42 lines
765 B
Markdown
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---
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title: Generate an Array of All Object Keys with Object.keys()
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localeTitle: 使用Object.keys()生成所有对象键的数组
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---
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## 使用Object.keys()生成所有对象键的数组
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### 方法:
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* 要返回用户数组, `Object.keys()`方法必须采用争论。
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* 可以使用单行返回语句来解决此挑战。
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### 解:
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```javascript
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let users = {
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Alan: {
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age: 27,
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online: false
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},
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Jeff: {
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age: 32,
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online: true
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},
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Sarah: {
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age: 48,
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online: false
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},
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Ryan: {
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age: 19,
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online: true
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}
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};
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function getArrayOfUsers(obj) {
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// change code below this line
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return Object.keys(obj);
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// change code above this line
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}
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console.log(getArrayOfUsers(users));
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```
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