92 lines
1.4 KiB
Markdown
92 lines
1.4 KiB
Markdown
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---
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id: 56bbb991ad1ed5201cd392d2
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title: 給 JavaScript 對象添加新屬性
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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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你也可以像更改屬性一樣給 JavaScript 對象添加屬性。
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這裏展示瞭如何給 `ourDog` 添加一個屬性 `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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現在，當我們執行 `ourDog.bark` 時，就能得到他的叫聲，`bow-wow`。
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例如：
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```js
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var 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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給 `myDog` 添加一個屬性 `bark` ，並將其設置爲狗的聲音，比如 “woof“。 可以使用點操作符或者中括號操作符。
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# --hints--
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應該給 `myDog` 添加屬性 `bark`。
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```js
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assert(myDog.bark !== undefined);
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```
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不應該在初始化部分添加 `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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// Setup
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var 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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// Only change code below this line
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```
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# --solutions--
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```js
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var 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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