private void combocent_SelectedIndexChanged(object sender, EventArgs e) { NumCentral = pr.GetNumber(combocent.Text); if (combocent.Text != CentrlName) { CentrlName = combocent.Text; Main.CabelInfo.Clear(); ComboType.Items.Clear(); MyList.Clear(); var DBonWork = new DB.SmartCentralDB(Properties.Settings.Default.ConctToDataBase); var SelectAllCabel = (from c in DBonWork.Cabels where c.IDcentral == NumCentral select new { c.IDCable, c.CableNumber }); foreach (var item in SelectAllCabel) { Main.CabelInfo.Add(item.IDCable, item.CableNumber); ComboType.Items.Add(item.CableNumber); } var j = from c in DBonWork.Cabels where c.IDcentral == NumCentral from p in DBonWork.Cabinas where p.IDCable == c.IDCable select p.CabinaGeneral; foreach (var item in j) { MyList.Add(item); } } if (button1.Text == "حفظ") { CabinaCabel.Clear(); } label6.Text = ""; ODU.Clear(); ComboType.Focus(); }