38 lines
		
	
	
		
			935 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			38 lines
		
	
	
		
			935 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
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								title: Do...While Loop
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								localeTitle: 做......循环
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								---
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								`do...while`循环与[`while`](http://forum.freecodecamp.com/t/javascript-while-loop/14668)循环密切相关。在do while循环中,在循环结束时检查条件。
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								这是`do...while`循环的**语法** :
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								## 句法:
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								```
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								 do { 
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								   *Statement(s);* 
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								 } while (*condition*); 
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								```
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								**statement(s):**在计算条件或布尔表达式之前**至少**执行**一次的**语句,并**在**每次条件计算结果为true时重新执行。
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								**condition:**这里,条件是布尔表达式 。如果布尔表达式的计算结果为true,则再次执行该语句。当布尔表达式求值为false时,循环结束。
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								## 例:
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								```
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								var i = 0; 
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								 do { 
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								  i = i + 1; 
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								  console.log(i); 
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								 } while (i < 5); 
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								 Output: 
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								 1 
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								 2 
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								 3 
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								 4 
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								 5 
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								```
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								来源: [**做......同时**](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/do…while)
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