46 lines
1015 B
Markdown
46 lines
1015 B
Markdown
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---
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title: Modify an Object Nested Within an Object
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localeTitle: 修改嵌套在对象中的对象
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---
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## 修改嵌套在对象中的对象
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方法：
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* 请记住，您想要更改的对象是两个级别， `dot-notation`在此实例中更容易使用。
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* 只需定义对象，然后使用`dot-notation`访问第二个对象，最后使用您想要修改的最终元素。
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## 例：
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```javascript
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let myObject = {
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level_1: 'outside',
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first_level_object: {
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level_2: '2 levels deep',
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second_level_object: {
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level_3: '3 levels deep'
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}
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}
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};
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//The following line of code will modify the data found in level_2.
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myObject.first_level_object.level_2 = 'level-2 has been reached';
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```
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## 解：
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```javascript
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let userActivity = {
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id: 23894201352,
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date: 'January 1, 2017',
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data: {
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totalUsers: 51,
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online: 42
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}
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};
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// change code below this line
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userActivity.data.online = 45;
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// change code above this line
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console.log(userActivity);
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```
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