' 1 Textbox      Text1
' 1 Textbox      Text4
' 1 Commandbuton Command3
'
Public Function DeleteCharFromPosition(ByVal sSource As String, ByVal _
  sDelFromHere As String) As String
    Dim lPosition As Long
       lPosition = InStr(sSource, sDelFromHere)
    If lPosition = 0 Then
       lPosition = Len(sSource) + 1
    End If
       DeleteCharFromPosition = RTrim$(Left$(sSource, lPosition - 1))
End Function
 
Private Sub Form_Load()
   Text4.Text = "("
End Sub
 
'AUFRUF:
Private Sub Command3_Click()
 Text1 = DeleteCharFromPosition(Text1, Text4)
End Sub