2021-05-05 10:13:49 -07:00
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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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2021-10-27 15:10:57 +00:00
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const ourDog = {
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2021-05-05 10:13:49 -07:00
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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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2021-05-10 01:12:02 +05:30
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不應該在 `myDog` 的初始化中添加 `bark`。
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2021-05-05 10:13:49 -07:00
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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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2021-05-10 01:12:02 +05:30
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2021-05-05 10:13:49 -07:00
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```
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# --solutions--
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```js
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2021-10-27 15:10:57 +00:00
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const myDog = {
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2021-05-05 10:13:49 -07:00
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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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