enum UDT's for compare

[packetVB]

I needed to be able to enumerate through the members of a large UDT to compare them with each other. Since VB has no way to do this I created my own and though others may care.

Only works with variants.

Public Type Test2
    aa As Variant
    bb As Variant
    cc As Variant
    dd As Variant
    ee As Variant
End Type
 
'Copy Memory Func
Public Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (ByRef pDest As Any, ByVal pSource As Any, ByVal Length As Long)
 
'VB own TypeName func, need to pass pointer
Public Declare Function rTypeName Lib "MSVBVM60.dll" Alias "rtcTypeName" (ByVal SS As Any) As String
 
'************************
'In: pass TWO vaptr(UDTvariable) 's to func call with size of UDT
'Out: String
Public Function CompareUDTs(UDTptr1 As Long, UDTptr2 As Long, UDTSize As Long) As String
Dim retString As String
Dim tempString As String
Dim StringPtr As Long
Dim i As Long
Dim VariantType1 As String
Dim VariantType2 As String
Dim tempVariant1 As Variant
Dim tempVariant2 As Variant
    Debug.Print UDTSize
    'each variant is 16 bytes long
    For i = 0 To UDTSize - 16 Step 16
        'lets determine the variant type for the fun of it
        VariantType1 = Replace(rTypeName(UDTptr1 + i), vbNullChar, "")
        VariantType2 = Replace(rTypeName(UDTptr2 + i), vbNullChar, "")
        Debug.Print VariantType1, VariantType2
        'now copy the current variant to the tempvariant
        CopyMemory tempVariant1, UDTptr1 + i, 16
        CopyMemory tempVariant2, UDTptr2 + i, 16
        Debug.Print ":" & tempVariant1, tempVariant2
        If tempVariant1 = tempVariant2 Then
            retString = retString & "Equal" & vbCrLf
        Else
            retString = retString & "Not Equal" & vbCrLf
        End If
    Next i
    Debug.Print retString
    CompareUDTs = retString
End Function
 
'****on FORM
Private Sub Command1_Click()
Dim ff As Test2
Dim cc As Test2
Dim aString As String
    ff.aa = "1"
    ff.bb = 200
    ff.cc = "a"
    ff.dd = 1
    ff.ee = 839
    
    cc.aa = "0923"
    cc.bb = 200
    cc.cc = "a"
    cc.dd = 10
    cc.ee = 839
    
    aString = CompareUDTs(VarPtr(ff), VarPtr(cc), Len(ff))
    Text1.Text = aString
End Sub