private void setoptionexistingpl() { MainMenu frm = new MainMenu(); //get data from table List <object[]> data = new List <object[]>(); data = frm.get_data_shipping_unit(1000); if (data.Count > 0) { cbexistingpl.Items.Clear(); for (int i = 0; i < data.Count; i++) { cbexistingpl.Items.Add(data[i][1].ToString()); } } }