Datumseingabe TTMMJJJJ - Ausgabe in TT.MM.JJJJ

Private Sub txtAntrag_Change()
Dim dteEingabe As Date
Dim iDay As Integer, iMonth As Integer, iYear As Integer
If txtAntrag.Text = "" Then Exit Sub
If Not IsNumeric(Right(txtAntrag.Text, 1)) Then
Beep
txtAntrag.SelStart = Len(txtAntrag.Text) - 1
txtAntrag.SelLength = 1
lblAusgabe.Caption = "Nur Ziffern erlaubt!"
Exit Sub
Else
lblAusgabe.Caption = ""
End If
iDay = CInt(Left(txtAntrag.Text, 2))
Select Case Len(txtAntrag.Text)
Case 0
Case 1
If iDay > 3 Then
Beep
txtAntrag.SelStart = 0
txtAntrag.SelLength = 1
lblAusgabe.Caption = "Maximal 31 Tage"
Else
lblAusgabe.Caption = ""
End If
Case 2
If iDay > 31 Then
Beep
txtAntrag.SelStart = 0
txtAntrag.SelLength = 2
lblAusgabe.Caption = "Maximal 31 Tage"
Else
lblAusgabe.Caption = ""
End If
Case 3
iMonth = CInt(Right(txtAntrag.Text, 1))
If iMonth > 1 Then
Beep
txtAntrag.SelStart = 2
txtAntrag.SelLength = 1
lblAusgabe.Caption = "Maximal 12 Monate"
Else
lblAusgabe.Caption = ""
End If
Case 4
iMonth = CInt(Right(txtAntrag.Text, 2))
If iMonth > 12 Then
Beep
txtAntrag.SelStart = 2
txtAntrag.SelLength = 2
lblAusgabe.Caption = "Maximal 12 Monate"
Else
lblAusgabe.Caption = ""
End If
Select Case iMonth
Case 2
If iDay > 29 Then
Beep
txtAntrag.SelStart = 0
txtAntrag.SelLength = 4
lblAusgabe.Caption = "Maximal 29 Tage"
Else
lblAusgabe.Caption = ""
End If
Case 4, 6, 9, 11
If iDay > 30 Then
Beep
txtAntrag.SelStart = 0
txtAntrag.SelLength = 4
lblAusgabe.Caption = "Maximal 30 Tage"
Else
lblAusgabe.Caption = ""
End If
End Select
Case 6
iMonth = CInt(Mid(txtAntrag.Text, 3, 2))
iYear = CInt(Right(txtAntrag.Text, 2))
If iYear Mod 4 > 0 And iMonth = 2 And iDay = 29 Then
Beep
txtAntrag.SelStart = 0
txtAntrag.SelLength = 6
lblAusgabe.Caption = "Maximal 28 Tage"
Else
txtAntrag.Text = DateSerial(iYear, iMonth, iDay)
dteEingabe = DateSerial(iYear, iMonth, iDay)
'lblAusgabe.Caption = dteEingabe & vbLf & Format(dteEingabe, "dddd")
txtAntrag.SelStart = 0
txtAntrag.SelLength = 6
'End If
txtFaelligkeit.SetFocus
txtFaelligkeit.SelStart = 0
txtFaelligkeit.SelLength = Len(txtFaelligkeit.Text)
End If
End Select
End Sub

Ich danke Euch.
Liebe Grüße aus Würzburg