Does VB6 short circuit conditional tests? That is to say, can I be sure a statement like...
If index <= array_si开发者_运维技巧ze And array(index) > something Then
will never burst the array, whatever the value of index might happen to be?
No, VB6's And
and Or
don't short-circuit (which is the reason why the short-circuit versions are called AndAlso
and OrElse
in VB.net — backward compatibility).
In addition to the If/Then/Else/End If
block, VB6 also supports a single-line If/Then/Else
construct. You can nest these to achieve simple short-circuiting. However, since it's a single-line statement, you must perform your desired action on the same line as well. For example:
' From (no short-circuit)
If index <= array_size And array(index) > something Then
' To (short-circuit)
If index <= array_size Then If array(index) > something Then ...
Select Case is a short circuit method if you can use it for your purpose.
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