c# - add to listview from diffrent sources -

c# - add to listview from diffrent sources -

i trying add together list view info different sources. have list view has 4 columns. in first 3 add together info query in lastly column want add together info combobox. here code:

private void buttonadauga_click(object sender, eventargs e) { sqlconnection conn = new sqlconnection("server=localhost;" + "trusted_connection=yes;" + "database=erp; " + "connection timeout=30"); sqlcommand cmd1 = new sqlcommand(); cmd1.commandtext = "select p.stoc [erp].[dbo].[produse] p, [erp].[dbo].[lista_preturi] lp, [erp].[dbo].[clienti] c denumire='"+combobox1.selecteditem+"' , p.cod_produs=lp.cod_produs , lp.id_lista=c.id_lista;"; cmd1.commandtype = commandtype.text; cmd1.connection = conn; conn.open(); sqldatareader reader; reader = cmd1.executereader(); int stoc=0; while(reader.read()) stoc = int32.parse(reader[0].tostring()); conn.close(); reader.dispose(); sqlcommand cmd = new sqlcommand(); cmd.commandtext = "select p.cod_produs, p.denumire, lp.pret [erp].[dbo].[produse] p, [erp].[dbo].[lista_preturi] lp, [erp].[dbo].[clienti] c p.denumire='" + combobox1.selecteditem + "' , p.cod_produs=lp.cod_produs , lp.id_lista=c.id_lista , c.nr_client="+decimal.parse(comboboxclienti.selecteditem.tostring())+";"; cmd.commandtype = commandtype.text; cmd.connection = conn; conn.open(); reader = cmd.executereader(); if (int32.parse(textboxcantitate.text) < stoc) { while (reader.read()) { listviewitem lvitem = new listviewitem(reader[0].tostring()); (int = 1; <= reader.fieldcount - 1; i++) { lvitem.subitems.add(reader[i].tostring()); } lvitem.subitems[3].text = combobox1.selectedvalue.tostring(); ----pt cantitati listview1.items.add(lvitem); } } else { messagebox.show("stocul maxim disponibil este "+stoc+".","atenție!",messageboxbuttons.ok); } }

it gives me error indexer if doesn't exist subitems[3]. suggestion?

c# sql-server listview