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---
id: 56533eb9ac21ba0edf2244cc
challengeType: 1
videoUrl: 'https://scrimba.com/c/cRnRnfa'
forumTopicId: 16161
localeTitle: 访问嵌套对象
---
## Description
<section id='description'>
通过串联起来的点操作符或中括号操作符来访问对象的嵌套属性。
下面是一个嵌套的对象:
```js
var ourStorage = {
"desk": {
"drawer": "stapler"
},
"cabinet": {
"top drawer": {
"folder1": "a file",
"folder2": "secrets"
},
"bottom drawer": "soda"
}
};
ourStorage.cabinet["top drawer"].folder2; // "secrets"
ourStorage.desk.drawer; // "stapler"
```
</section>
## Instructions
<section id='instructions'>
读取<code>myStorage</code>对象,将<code>glove box</code>属性的内容赋值给变量<code>gloveBoxContents</code>。在适用的地方使用点操作符来访问属性,否则使用中括号操作符。
</section>
## Tests
<section id='tests'>
```yml
tests:
- text: <code>gloveBoxContents</code>应该等于"maps"。
testString: assert(gloveBoxContents === "maps");
- text: 应使用点操作符和中括号操作符来访问<code>myStorage</code>
testString: assert(/=\s*myStorage\.car\.inside\[\s*("|')glove box\1\s*\]/g.test(code));
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='js-seed'>
```js
// Setup
var myStorage = {
"car": {
"inside": {
"glove box": "maps",
"passenger seat": "crumbs"
},
"outside": {
"trunk": "jack"
}
}
};
var gloveBoxContents = undefined; // Change this line
```
</div>
### After Test
<div id='js-teardown'>
```js
(function(x) {
if(typeof x != 'undefined') {
return "gloveBoxContents = " + x;
}
return "gloveBoxContents is undefined";
})(gloveBoxContents);
```
</div>
</section>
## Solution
<section id='solution'>
```js
var myStorage = {
"car":{
"inside":{
"glove box":"maps",
"passenger seat":"crumbs"
},
"outside":{
"trunk":"jack"
}
}
};
var gloveBoxContents = myStorage.car.inside["glove box"];
```
</section>