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isArrayEmpty.bas
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/
isArrayEmpty.bas
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Attribute VB_Name = "isArrayEmpty"
Public Function isArrayEmpty(ByRef Arr As Variant) As Boolean
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' IsArrayEmpty
' This function tests whether the array is empty (unallocated). Returns TRUE or FALSE.
'
' The VBA IsArray function indicates whether a variable is an array, but it does not
' distinguish between allocated and unallocated arrays. It will return TRUE for both
' allocated and unallocated arrays. This function tests whether the array has actually
' been allocated.
'
' This function is really the reverse of IsArrayAllocated.
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Dim LB As Long
Dim UB As Long
Err.Clear
On Error GoTo ErrorHandler
If IsArray(Arr) = False Then
' we weren't passed an array, return True
isArrayEmpty = True
End If
' Attempt to get the UBound of the array. If the array is
' unallocated, an error will occur.
UB = UBound(Arr, 1)
If (Err.Number <> 0) Then
isArrayEmpty = True
Else
''''''''''''''''''''''''''''''''''''''''''
' On rare occassion, under circumstances I
' cannot reliably replictate, Err.Number
' will be 0 for an unallocated, empty array.
' On these occassions, LBound is 0 and
' UBoung is -1.
' To accomodate the weird behavior, test to
' see if LB > UB. If so, the array is not
' allocated.
''''''''''''''''''''''''''''''''''''''''''
Err.Clear
LB = LBound(Arr)
isArrayEmpty = LB > UB
End If
Exit Function
ErrorHandler:
If Err.Number > 0 Then 'TODO: handle specific error
Err.Clear
Resume Next
End If
End Function