23 lines
611 B
Markdown
23 lines
611 B
Markdown
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---
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title: Spread Operator
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localeTitle: 传播运营商
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---
## 传播运营商
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扩展运算符（ `...` ）允许获取集合的元素。
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最常见的用途之一是`Node` Objects，当在浏览器中使用查询选择器时，为了使它们成为可迭代的数组对象：
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```javascript
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const paragraphs = document.querySelectorAll('p.paragraph');
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const arr = [...paragraphs];
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```
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扩展运算符的另一个用途是用于数组连接：
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```javascript
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const arr_1 = [1, 2, 3, 4]
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const arr_2 = [5, 6, 7, 8]
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const arr_final = [...arr_1, ...arr_2]
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// arr_final = [1, 2, 3, 4, 5, 6, 7, 8]
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```
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