Option Explicit

Private Feld(1 To 10)
Private DataAscending As Boolean

Enum EnumFilter
  NoFilter
  GetAllNumbers
  GetFirstNumbers
  GetLastNumbers
End Enum

Private Sub Form_Load()
  Dim x As Integer

  InitData

  For x = 1 To 10
    List1.AddItem Feld(x%)
  Next
End Sub

Private Sub InitData()
  Feld(1) = "2324abc3"
  Feld(2) = "324aaa1"
  Feld(3) = "24cde2"
  Feld(4) = "2agh9"
  Feld(5) = "23caa7"
  Feld(6) = "132kla6"
  Feld(7) = "557mna5"
  Feld(8) = "555man10"
  Feld(9) = "8988bcd4"
  Feld(10) = "4222feda8"
End Sub

Private Sub optSort_Click(Index As Integer)
  Dim DataAscending As Boolean

  Dim Filterstil As EnumFilter
  Dim x As Integer

  InitData

  List2.Clear
  List3.Clear

  If chkAscending = 1 Then
      DataAscending = True
    Else
      DataAscending = False
  End If

  Select Case Index
    Case 0
       'keine Sortierung
    Case 1
      Sort Feld(), DataAscending, NoFilter
    Case 2
      Sort Feld(), DataAscending, GetAllNumbers
    Case 3
      Sort Feld(), DataAscending, GetFirstNumbers
    Case 4
      Sort Feld(), DataAscending, GetLastNumbers
  End Select

  For x% = 1 To 10
    List2.AddItem Feld(x%)
    If Index > 1 Then
      Select Case Index
         Case 2: Filterstil = GetAllNumbers
         Case 3: Filterstil = GetFirstNumbers
         Case 4: Filterstil = GetLastNumbers
      End Select
      List3.AddItem NumFilter$(CStr(Feld(x%)), Filterstil)
    Else
      List3.AddItem Feld(x%)
    End If
  Next x
End Sub

Private Sub chkAscending_Click()
  Dim x As Integer

  If chkAscending = 1 Then
    DataAscending = True
  Else
    DataAscending = False
  End If

  For x% = 0 To 4
    If optSort(x).Value = True Then
      optSort_Click x
      Exit For
    End If
  Next x%
End Sub

Private Sub Sort(Data() As Variant, Ascending As Boolean, _
        StringSort As EnumFilter)

  Dim TempValue As Variant
  Dim Element As Long
  Dim Counter As Long

  For Element = LBound(Data) To UBound(Data)
    For Counter = Element + 1 To UBound(Data)
      If Ascending Then
        If VarType(Data(Element&)) = vbString And _
                StringSort <> NoFilter Then
          If Val(NumFilter$(CStr(Data(Element&)), StringSort)) > _
             Val(NumFilter$(CStr(Data(Counter&)), StringSort)) Then
            TempValue = Data(Element&)
            Data(Element&) = Data(Counter&)
            Data(Counter&) = TempValue
          End If
        Else
          If Data(Element&) > Data(Counter) Then
            TempValue = Data(Element)
            Data(Element) = Data(Counter)
            Data(Counter&) = TempValue
          End If
        End If
      Else
        If VarType(Data(Element)) = vbString _
              And StringSort <> NoFilter Then
          If Val(NumFilter$(CStr(Data(Element&)), StringSort)) < _
             Val(NumFilter$(CStr(Data(Counter&)), StringSort)) Then
            TempValue = Data(Element)
            Data(Element) = Data(Counter)
            Data(Counter) = TempValue
          End If
        Else
          If Data(Element&) < Data(Counter&) Then
            TempValue = Data(Element&)
            Data(Element&) = Data(Counter&)
            Data(Counter&) = TempValue
          End If
        End If
      End If
    Next Counter
  Next Element
End Sub

Private Function NumFilter(Text As String, _
        Filterstyle As EnumFilter) As String

  Dim x As Long
  Dim Zeichen As String
  Dim Temp As String

  If Filterstyle = GetAllNumbers Then
    For x = 1 To Len(Text$)
      Zeichen$ = Mid$(Text$, x, 1)
      If Asc(Zeichen$) >= 48 And Asc(Zeichen$) <= 57 Then
        Temp$ = Temp$ & Zeichen$
      End If
    Next x

  ElseIf Filterstyle = GetFirstNumbers Then
    For x = 1 To Len(Text$)
      Zeichen$ = Mid$(Text$, x, 1)
      If Asc(Zeichen$) >= 48 And Asc(Zeichen$) <= 57 Then
        Temp$ = Temp$ & Zeichen$
      Else
        If Temp$ <> "" Then Exit For
      End If
    Next x

  ElseIf Filterstyle = GetLastNumbers Then
    For x = Len(Text$) To 1 Step -1
      Zeichen$ = Mid$(Text$, x, 1)
      If Asc(Zeichen$) >= 48 And Asc(Zeichen$) <= 57 Then
        Temp$ = Zeichen$ & Temp$
      Else
        If Temp$ <> "" Then Exit For
      End If
    Next
  End If

  NumFilter$ = Temp$
End Function