23 lines
		
	
	
		
			611 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			23 lines
		
	
	
		
			611 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| ---
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| title: Spread Operator
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| localeTitle: 传播运营商
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| ---
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| ## 传播运营商
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| 
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| 扩展运算符( `...` )允许获取集合的元素。
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| 
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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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| 
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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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| 
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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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| 
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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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| ``` |