99 lines
1.8 KiB
Markdown
99 lines
1.8 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244cc
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title: 访问嵌套对象
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cRnRnfa'
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forumTopicId: 16161
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dashedName: accessing-nested-objects
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---
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# --description--
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我们可以通过连续使用点号表示法和方括号表示法来访问对象的嵌套属性。
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这是一个访问嵌套对象的示例：
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```js
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var ourStorage = {
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"desk": {
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"drawer": "stapler"
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},
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"cabinet": {
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"top drawer": {
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"folder1": "a file",
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"folder2": "secrets"
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},
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"bottom drawer": "soda"
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}
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};
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ourStorage.cabinet["top drawer"].folder2; // "secrets"
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ourStorage.desk.drawer; // "stapler"
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```
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# --instructions--
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请把 `myStorage` 对象中 `glove box` 的属性值赋给变量 `gloveBoxContents`。请优先使用点号表示法来访问属性；对于点号表示法不能处理的情况，再考虑使用方括号表示法。
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# --hints--
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`gloveBoxContents` 的值应为 "maps"。
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```js
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assert(gloveBoxContents === 'maps');
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```
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应使用点号表示法和方括号表示法来访问 `myStorage`。
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```js
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assert(/=\s*myStorage\.car\.inside\[\s*("|')glove box\1\s*\]/g.test(code));
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```
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# --seed--
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## --after-user-code--
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```js
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(function(x) {
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if(typeof x != 'undefined') {
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return "gloveBoxContents = " + x;
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}
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return "gloveBoxContents is undefined";
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})(gloveBoxContents);
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```
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## --seed-contents--
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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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# --solutions--
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```js
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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 = myStorage.car.inside["glove box"];
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```
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