2021-05-05 10:13:49 -07:00
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---
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id: 56533eb9ac21ba0edf2244cb
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title: 操作複雜對象
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/c9yNMfR'
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forumTopicId: 18208
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dashedName: manipulating-complex-objects
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---
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# --description--
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有時你可能希望將數據存儲在一個靈活的數據結構(<dfn>Data Structure</dfn>)中。 JavaScript 對象是一種靈活的數據結構。 它可以儲存字符串(<dfn>strings</dfn>)、數字(<dfn>numbers</dfn>)、布爾值(<dfn>booleans</dfn>)、數組(<dfn>arrays</dfn>)、函數(<dfn>functions</dfn>)和對象(<dfn>objects</dfn>)以及這些值的任意組合。
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這是一個複雜數據結構的示例:
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```js
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2021-10-27 15:10:57 +00:00
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const ourMusic = [
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2021-05-05 10:13:49 -07:00
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{
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"artist": "Daft Punk",
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"title": "Homework",
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"release_year": 1997,
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"formats": [
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"CD",
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"Cassette",
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"LP"
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],
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"gold": true
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}
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];
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```
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2021-09-30 07:29:50 -07:00
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這是一個包含一個對象的數組。 該對象有關於專輯的各種元數據(<dfn>metadata</dfn>)。 它也有一個嵌套的 `formats` 數組。 可以將專輯添加到頂級數組來增加更多的專輯記錄。 對象將數據以一種鍵 - 值對的形式保存。 在上面的示例中,`"artist": "Daft Punk"` 有一個鍵爲 `artist` 值爲 `Daft Punk` 的屬性。 [JavaScript Object Notation](http://www.json.org/) 簡稱 `JSON` 是可以用於存儲數據的數據交換格式。
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2021-05-05 10:13:49 -07:00
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```json
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{
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"artist": "Daft Punk",
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"title": "Homework",
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"release_year": 1997,
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"formats": [
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"CD",
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"Cassette",
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"LP"
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],
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"gold": true
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}
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```
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**提示:**數組中有多個 JSON 對象的時候,對象與對象之間要用逗號隔開。
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# --instructions--
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添加一個新專輯到 `myMusic` 數組。 添加 `artist` 和 `title` 字符串,`release_year` 數字和 `formats` 字符串數組。
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# --hints--
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`myMusic` 應該是一個數組
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```js
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assert(Array.isArray(myMusic));
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```
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2021-05-10 01:12:02 +05:30
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`myMusic`應該有至少2個元素。
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```js
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assert(myMusic.length > 1);
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```
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2021-05-10 01:12:02 +05:30
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`myMusic`元素數組中應該是物體
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```js
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myMusic.forEach(object => {assert.typeOf(object, 'object')})
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```
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2021-05-10 01:12:02 +05:30
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`myMusic` 中的對象應該至少有 4 個屬性。
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```js
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myMusic.forEach(object => {assert(Object.keys(object).length > 3); });
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```
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2021-05-10 01:12:02 +05:30
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`myMusic` 中的對象應該包含一個類型爲字符串的屬性 `artist`。
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```js
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myMusic.forEach(object => {
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assert.containsAllKeys(object, ['artist']);
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assert.typeOf(object.artist, 'string')
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})
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```
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2021-05-10 01:12:02 +05:30
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`myMusic` 中的對象應該包含一個類型爲字符串的屬性 `title`。
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```js
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myMusic.forEach(object => {
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assert.containsAllKeys(object, ['title']);
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assert.typeOf(object.title, 'string')
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})
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```
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2021-05-10 01:12:02 +05:30
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`myMusic` 中的對象應該包含一個類型爲數字的屬性 `release_year`。
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2021-05-05 10:13:49 -07:00
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```js
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myMusic.forEach(object => {
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assert.containsAllKeys(object, ['release_year']);
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assert.typeOf(object.release_year, 'number')
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})
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```
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2021-05-10 01:12:02 +05:30
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`myMusic` 中的對象應該包含一個類型爲數組的 `formats` 屬性。
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2021-05-05 10:13:49 -07:00
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```js
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myMusic.forEach(object => {
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assert.containsAllKeys(object, ['formats']);
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assert.typeOf(object.formats, 'array')
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})
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```
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`formats`應該是一個至少包含兩個字符串元素的數組
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```js
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2021-05-10 01:12:02 +05:30
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myMusic.forEach(object => {
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object.formats.forEach(format => {
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assert.typeOf(format, 'string')
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});
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assert.isAtLeast(object.formats.length, 2)
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})
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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){ if (Array.isArray(x)) { return JSON.stringify(x); } return "myMusic is not an array"})(myMusic);
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```
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## --seed-contents--
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```js
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2021-10-27 15:10:57 +00:00
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const myMusic = [
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{
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"artist": "Billy Joel",
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"title": "Piano Man",
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"release_year": 1973,
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"formats": [
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"CD",
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"8T",
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"LP"
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],
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"gold": true
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}
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];
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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 myMusic = [
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2021-05-05 10:13:49 -07:00
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{
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"artist": "Billy Joel",
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"title": "Piano Man",
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"release_year": 1973,
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"formats": [
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"CS",
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"8T",
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"LP" ],
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"gold": true
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},
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{
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"artist": "ABBA",
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"title": "Ring Ring",
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"release_year": 1973,
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"formats": [
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"CS",
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"8T",
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"LP",
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"CD",
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]
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}
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];
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```
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