Dim colnames() As String = {"Kategorie", "Details", "Wert*", "fällig*", _
  "Laufzeitende", "ausschließen"}
        DGV1.Columns.Clear()
 
        For j As Integer = 0 To 5
 
            If j = 0 Or j = 3 Then
                Dim comboboxCol As New DataGridViewComboBoxColumn
                With comboboxCol
                    .HeaderText = colnames(j)
                    .DisplayStyle = DataGridViewComboBoxDisplayStyle.ComboBox
                    .DisplayStyleForCurrentCellOnly = True
                    If j = 0 Then .DataSource = Kategorien
                    If j = 3 Then .DataSource = Faellig
                    .FlatStyle = FlatStyle.Flat
                    .DropDownWidth = 120
                    .Width = 120
                    .MaxDropDownItems = 15
                End With
 
                DGV1.Columns.Add(CType(comboboxCol, DataGridViewColumn))
 
            End If
 
            If j = 1 Or j = 2 Or j = 4 Then
                Dim dgvcol As New DataGridViewTextBoxColumn
                dgvcol.HeaderText = colnames(j)
                DGV1.Columns.Add(dgvcol)
                If j = 2 Then DGV1.Columns(j).ValueType = GetType(System.Double)
 
            End If
 
            If j = 5 Then
                Dim dgvcol As New DataGridViewCheckBoxColumn
                dgvcol.HeaderText = colnames(j)
                DGV1.Columns.Add(dgvcol)
            End If
 
        Next j