16 lines
572 B
Markdown
16 lines
572 B
Markdown
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---
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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。
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