Add extra row to datagridviewcombobox

See more:

combobox

DataGridView

DataRow

I have defined this datagridviewcombobox:

Dim lCol2 As New DataGridViewComboBoxColumn
lCol2.DataPropertyName = "Descrizione"
lCol2.DisplayMember = "Descrizione"
lCol2.ValueMember = "IDTessera"
lCol2.DisplayIndex = 2
dgwNote.Columns.Add(lCol2)

then I filled the combo this way:

sql = "SELECT Descrizione,IDTessera FROM T01_TipiDoc ORDER BY Descrizione"
DA = New OleDbDataAdapter(sql, Connect.Conn)
DA.Fill(DT)

Dim dv As New DataView(DT)

and this works normally

What I have tried:

I would like add an extra row at the end of the list, so, after DA.Fill(DT), I added this:

DT.Rows.Add("NEW", DT.Rows.Count + 1)

but this is wrong

anyone think is possible to have a work around this?
thank