private void completezComboboxTransport_Alocare()
 {
     comboBoxTransport.Items.Clear();
     transportDT = Interogari_DB.selectezTransport();
     comboBoxTransport.DataSource    = transportDT;
     comboBoxTransport.ValueMember   = "cod_tr";
     comboBoxTransport.DisplayMember = "denumire_mat_tr";
 }