Safe UBound and LBound
Ever wanted to use LBound and UBound to get arrays boundaries without jumping over error message when the array is empty? These functions will replace the ordinary LBound and UBound procedures so you don’t need to worry about errors. I've also included a way to get the dimensions of an array. Just paste the following code into a module, and the problem is solved.
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Source Code
Option Explicit
Declare Function VarPtrArray Lib "msvbvm50.dll" Alias "VarPtr" (Ptr() As Any) As Long
Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Any, Source As Any, ByVal Length As Long)
Public Function SafeUBound(ByVal lpArray As Long, Optional Dimension As Long = 1) As Long
Dim lAddress&, cElements&, lLbound&, cDims%
If Dimension < 1 Then
SafeUBound = -1
Exit Function
End If
CopyMemory lAddress, ByVal lpArray, 4
If lAddress = 0 Then
' The array isn't initilized
SafeUBound = -1
Exit Function
End If
' Calculate the dimensions
CopyMemory cDims, ByVal lAddress, 2
Dimension = cDims - Dimension + 1
' Obtain the needed data
CopyMemory cElements, ByVal (lAddress + 16 + ((Dimension - 1) * 8)), 4
CopyMemory lLbound, ByVal (lAddress + 20 + ((Dimension - 1) * 8)), 4
SafeUBound = cElements + lLbound - 1
End Function
Public Function SafeLBound(ByVal lpArray As Long, Optional Dimension As Long = 1) As Long
Dim lAddress&, cElements&, lLbound&, cDims%
If Dimension < 1 Then
SafeLBound = -1
Exit Function
End If
CopyMemory lAddress, ByVal lpArray, 4
If lAddress = 0 Then
' The array isn't initilized
SafeLBound = -1
Exit Function
End If
' Calculate the dimensions
CopyMemory cDims, ByVal lAddress, 2
Dimension = cDims - Dimension + 1
' Obtain the needed data
CopyMemory lLbound, ByVal (lAddress + 20 + ((Dimension - 1) * 8)), 4
SafeLBound = lLbound
End Function
Public Function ArrayDims(ByVal lpArray As Long) As Integer
Dim lAddress As Long
CopyMemory lAddress, ByVal lpArray, 4
If lAddress = 0 Then
' The array isn't initilized
ArrayDims = -1
Exit Function
End If
CopyMemory ArrayDims, ByVal lAddress, 2
End Function
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