IMP和EQV在VB6中的逻辑功能是什么？有没有人为他们找到真实世界的用途？

Question

And,Or,Xor和Not我明白了.我没有得到的是Imp和Eqv.他们的意思是什么？他们怎么进去的？它们真的有用吗？

Answer 1

IMP是"物质含义""a暗示b"或"如果a然后b",它相当于NOT OR OR b.EQV是"等价的"或"当且仅当",因此EQV b与(a IMP b)AND(b IMP a)相同.

他们到了那里因为有人想完成.它们可以缩短一些逻辑表达式,但是你总是可以用NOT和AND,NOT和OR表示相同的东西,或者单独使用XOR.

Answer 2

这是所有运算符的真值表，包括布尔运算符和按位运算符。使用它们的最佳时间是当您映射逻辑并意识到您有一个接受两个输入的函数时，并且具有与这些运算符相同的输出:)

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|AND  |     |     |     |OR   |     |     |     |XOR  |     |     |     |IMP  |     |     |     |EQV  |     |     |
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|In1  |In2  |Out1 |     |In1  |In2  |Out1 |     |In1  |In2  |Out1 |     |In1  |In2  |Out1 |     |In1  |In2  |Out1 |
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|False|False|False|     |False|False|False|     |False|False|False|     |False|False|True |     |False|False|True |
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|False|True |False|     |False|True |True |     |False|True |True |     |False|True |True |     |False|True |False|
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|False|Null |False|     |False|Null |Null |     |False|Null |Null |     |False|Null |True |     |False|Null |Null |
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|True |False|False|     |True |False|True |     |True |False|True |     |True |False|False|     |True |False|False|
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|True |True |True |     |True |True |True |     |True |True |False|     |True |True |True |     |True |True |True |
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|True |Null |Null |     |True |Null |True |     |True |Null |Null |     |True |Null |Null |     |True |Null |Null |
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|Null |False|False|     |Null |False|Null |     |Null |False|Null |     |Null |False|Null |     |Null |False|Null |
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|Null |True |Null |     |Null |True |True |     |Null |True |Null |     |Null |True |True |     |Null |True |Null |
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|Null |Null |Null |     |Null |Null |Null |     |Null |Null |Null |     |Null |Null |Null |     |Null |Null |Null |
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|     |     |     |     |     |     |     |     |     |     |     |     |     |     |     |     |     |     |     |
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|In1  |In2  |Out1 |     |In1  |In2  |Out1 |     |In1  |In2  |Out1 |     |In1  |In2  |Out1 |     |In1  |In2  |Out1 |
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|001  |001  |001  |     |001  |001  |001  |     |001  |001  |000  |     |001  |001  |111  |     |001  |001  |111  |
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|001  |010  |000  |     |001  |010  |011  |     |001  |010  |011  |     |001  |010  |110  |     |001  |010  |100  |
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|001  |011  |001  |     |001  |011  |011  |     |001  |011  |010  |     |001  |011  |111  |     |001  |011  |101  |
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|001  |100  |000  |     |001  |100  |101  |     |001  |100  |101  |     |001  |100  |110  |     |001  |100  |010  |
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|010  |001  |000  |     |010  |001  |011  |     |010  |001  |011  |     |010  |001  |101  |     |010  |001  |100  |
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|010  |010  |010  |     |010  |010  |010  |     |010  |010  |000  |     |010  |010  |111  |     |010  |010  |111  |
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|010  |011  |010  |     |010  |011  |011  |     |010  |011  |001  |     |010  |011  |111  |     |010  |011  |110  |
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|010  |100  |000  |     |010  |100  |110  |     |010  |100  |110  |     |010  |100  |101  |     |010  |100  |001  |
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|011  |001  |001  |     |011  |001  |011  |     |011  |001  |010  |     |011  |001  |101  |     |011  |001  |101  |
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|011  |010  |010  |     |011  |010  |011  |     |011  |010  |001  |     |011  |010  |110  |     |011  |010  |110  |
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|011  |011  |011  |     |011  |011  |011  |     |011  |011  |000  |     |011  |011  |111  |     |011  |011  |111  |
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|011  |100  |000  |     |011  |100  |111  |     |011  |100  |111  |     |011  |100  |100  |     |011  |100  |000  |
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