74 lines
2.0 KiB
Markdown
74 lines
2.0 KiB
Markdown
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---
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id: 56533eb9ac21ba0edf2244cc
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title: Accessing Nested Objects
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challengeType: 1
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guideUrl: 'https://chinese.freecodecamp.org/guide/certificates/accessing-nested-objects-in-json'
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videoUrl: ''
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localeTitle: 访问嵌套对象
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---
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## Description
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<section id="description">可以通过将点或括号表示法链接在一起来访问对象的子属性。这是一个嵌套对象： <blockquote> var ourStorage = { <br> “桌子”：{ <br> “抽屉”：“订书机” <br> }， <br> “内阁”：{ <br> “顶级抽屉”：{ <br> “folder1”：“一个文件”， <br> “folder2”：“秘密” <br> }， <br> “底部抽屉”：“苏打水” <br> } <br> }; <br> ourStorage.cabinet [“top drawer”]。folder2; //“秘密” <br> ourStorage.desk.drawer; //“订书机” </blockquote></section>
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## Instructions
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<section id="instructions">访问<code>myStorage</code>对象并将<code>glove box</code>属性的内容分配给<code>gloveBoxContents</code>变量。对于名称中包含空格的属性，请使用括号表示法。 </section>
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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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- text: <code>gloveBoxContents</code>应该等于“地图”
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testString: 'assert(gloveBoxContents === "maps", "<code>gloveBoxContents</code> should equal "maps"");'
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- text: 使用点和括号表示法访问<code>myStorage</code>
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testString: 'assert(/=\s*myStorage\.car\.inside\[\s*("|")glove box\1\s*\]/g.test(code), "Use dot and bracket notation to access <code>myStorage</code>");'
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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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// Setup
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var myStorage = {
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"car": {
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"inside": {
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"glove box": "maps",
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"passenger seat": "crumbs"
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},
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"outside": {
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"trunk": "jack"
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}
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}
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};
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var gloveBoxContents = undefined; // Change this line
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```
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</div>
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### After Test
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<div id='js-teardown'>
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```js
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console.info('after the test');
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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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// solution required
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```
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</section>
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