How to check for empty array in vba macro [duplicate]

Go with a triple negative:

If (Not Not FileNamesList) <> 0 Then
    ' Array has been initialized, so you're good to go.
Else
    ' Array has NOT been initialized
End If

Or just:

If (Not FileNamesList) = -1 Then
    ' Array has NOT been initialized
Else
    ' Array has been initialized, so you're good to go.
End If

In VB, for whatever reason, Not myArray returns the SafeArray pointer. For uninitialized arrays, this returns -1. You can Not this to XOR it with -1, thus returning zero, if you prefer.

               (Not myArray)   (Not Not myArray)
Uninitialized       -1                 0
Initialized    -someBigNumber   someOtherBigNumber

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