69 lines
1.2 KiB
Markdown
69 lines
1.2 KiB
Markdown
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---
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title: Accessing Nested Arrays
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localeTitle: 访问嵌套数组
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---
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## 访问嵌套数组
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### 使用括号表示法`[]`访问数组中的元素
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```js
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var fruitBasket = ['apple', 'banana' 'orange', 'melon'];
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var favoriteFruit = fruitBasket[2];
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console.log(favoriteFruit) // 'orange'
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```
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在这个例子中，我们最喜欢的水果是'orange'，它位于`fruitBasket`数组的索引`2` 。使用braket表示法，我们将`fruitBasket`数组的索引`2`分配给`favoriteFruit` 。这使得`favoriteFruit`等于'orange'。
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### 使用braket `[]`和dot访问数组中的对象`.`符号
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```js
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var garage = [
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{
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type: 'car',
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color: 'red',
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make: 'Ford'
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},
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{
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type: 'motorbike',
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color: 'black',
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make: 'Yamaha'
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},
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{
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type: 'bus',
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color: 'yellow',
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make: 'Blue Bird'
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}
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];
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var busColor = garage[2].color; // 'yellow'
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```
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## 解：
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```js
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// Setup
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var myPlants = [
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{
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type: "flowers",
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list: [
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"rose",
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"tulip",
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"dandelion"
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]
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},
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{
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type: "trees",
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list: [
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"fir",
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"pine",
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"birch"
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]
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}
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];
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// Only change code below this line
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var secondTree = myPlants[1].list[1];
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```
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