Private mColStringMethode As New AutoCompleteStringCollection
 
Private Sub Autocompleteliste_erstellen
   ..
   mColStringMethode.Add(Teile(0) & " - " & Teile(3))
   ..
end sub
 
Private Sub DGV_EditingControlShowing(ByVal sender As Object, ...)
    If DGV.Columns(DGV.CurrentCell.ColumnIndex).Name = "Methode" Then
        With DirectCast(e.Control, TextBox)
            .AutoCompleteMode = AutoCompleteMode.SuggestAppend
            .AutoCompleteSource = AutoCompleteSource.CustomSource
            .AutoCompleteCustomSource = mColStringMethode
            'Weite  der AutocompleteListe vergrößern
            .width = 300  'funktioniert nicht
        End With
    End If
End Sub