Understanding automation : How is automation coding structured? : Using Boolean comparison and assignment
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| Understanding automation : How is automation coding structured? : Using Boolean comparison and assignment |
In Microsoft Visual Basic (VB), Boolean comparison and Boolean assignment are both performed by using a single equals sign ( = ):
If a = b Then c = d |
By contrast, many other languages use a double equals sign for Boolean comparison and a single equals sign for Boolean assignment:
if( a == b ) c = d; |
The following code, which is valid in C, C++, Java, and JavaScript, is invalid in VBA:
if( ( result = fooBar( ) ) == true ) |
The preceding example would be written in VBA as the following:
result = fooBar( ) |
If result = True Then |
For other Boolean comparisons, VBA uses the same operators as other languages (except for the operators for “is equal to” and “is not equal to”). All the Boolean-comparison operators are provided in the following table.
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Comparison
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VBA operator
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C-style operator
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|---|---|---|
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Is equal to
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=
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==
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Is not equal to
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<>
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!=
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Is greater than
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>
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>
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Is less than
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<
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<
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Is greater than or equal to
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>=
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>=
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Is less than or equal to
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<=
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<=
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The result of using a Boolean operator is always either True or False.
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