91 lines
1.4 KiB
Markdown
91 lines
1.4 KiB
Markdown
---
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id: 56bbb991ad1ed5201cd392d2
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title: 给 JavaScript 对象添加新属性
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cQe38UD'
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forumTopicId: 301169
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dashedName: add-new-properties-to-a-javascript-object
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---
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# --description--
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你也可以像更改属性一样给 JavaScript 对象添加属性。
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这里展示了如何给 `ourDog` 添加一个属性 `bark`：
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```js
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ourDog.bark = "bow-wow";
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```
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或者
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```js
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ourDog["bark"] = "bow-wow";
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```
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现在，当我们执行 `ourDog.bark` 时，就能得到他的叫声，`bow-wow`。
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例如：
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```js
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const ourDog = {
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"name": "Camper",
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"legs": 4,
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"tails": 1,
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"friends": ["everything!"]
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};
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ourDog.bark = "bow-wow";
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```
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# --instructions--
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给 `myDog` 添加一个属性 `bark` ，并将其设置为狗的声音，比如 “woof“。 可以使用点操作符或者中括号操作符。
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# --hints--
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应该给 `myDog` 添加属性 `bark`。
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```js
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assert(myDog.bark !== undefined);
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```
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不应该在 `myDog` 的初始化中添加 `bark`。
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```js
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assert(!/bark[^\n]:/.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(z){return z;})(myDog);
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```
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## --seed-contents--
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```js
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const myDog = {
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"name": "Happy Coder",
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"legs": 4,
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"tails": 1,
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"friends": ["freeCodeCamp Campers"]
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};
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```
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# --solutions--
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```js
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const myDog = {
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"name": "Happy Coder",
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"legs": 4,
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"tails": 1,
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"friends": ["freeCodeCamp Campers"]
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};
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myDog.bark = "Woof Woof";
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```
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