<asp:ButtonColumn Text="Cancella" ButtonType="PushButton" HeaderText="Delete?" CommandName="delete">

<ASPATAGRID id="MyDataGrid" runat="server" DataKeyField="Codice" OnDeleteCommand="MyDataGrid_Delete"...>

sub MyDataGrid_Delete(Sender As Object, E As DataGridCommandEventArgs)

chiave_record_Selezionato = MyDataGrid.DataKeys(E.Item.ItemIndex

end sub