IMP和EQV在VB6中的逻辑函数如何?有没有人找到现实世界的使用?
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06-09-2019 - |
解决方案
IMP是“材料的含义”“ A表示B”或“如果A则为B”,这等同于A或B。 eqv是“等效性”或“仅在且仅在”的情况下,因此EQV B与(A IMP B)和(B IMP A)相同。
他们到那里是因为有人想完整。他们可以缩短一些逻辑表达式,但是您总是可以不用和,或者与Xor单独表达同一件事。
其他提示
这是所有操作员的真实表,无论是布尔值还是位于钻石。使用它们的最佳时间是绘制逻辑并意识到自己具有两个输入的函数,并且与这些运算符的输出相同:)
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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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iirc,他们都在两个输入上执行一个位!XOR,然后返回结果。
它们不存在于任何一个.NET代码库中(除非您计算VB6兼容性层库),因此应考虑弃用并因此被忽略。
在我的头顶上,我不能说,因为我曾经使用过它们。
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