16 lines
		
	
	
		
			572 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			16 lines
		
	
	
		
			572 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
---
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title: instanceof Operator
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localeTitle: instanceof运算符
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---
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# `instanceof`运算符
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`instanceof`运算符允许您检查`IS A`关系的有效性。如果在任何时候,我们不确定这一点,并且我们想在运行时验证这一点,我们可以执行以下操作:
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```java
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//assuming vehicle is an instance of Class `Car` the expression inside the 'if' will  return true 
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 if(vehicle instanceof Car){ 
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    //do something if vehicle is a Car 
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 } 
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```
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**注意** :如果将instanceof运算符应用于具有null值的任何变量,则返回false。 |