private void cboxProduct_TextChanged(object sender, EventArgs e) { List <string> lst = new List <string>(); foreach (DataRow d in preProductSize.loadProductDT(false).Rows) { if ((d[0].ToString() + " - " + d[1].ToString()).ToLower().Contains(cboxProduct.Text.ToString().ToLower())) { lst.Add(d[0].ToString() + " - " + d[1].ToString()); } } cboxProduct.Properties.Items.Clear(); cboxProduct.Properties.Items.AddRange(lst); try { cboxProduct.ShowPopup(); } catch (Exception ex) { } foreach (DataRow d in preProductSize.loadProductDT(false).Rows) { if (cboxProduct.Text.Contains(d[0].ToString()) && cboxProduct.Text.Contains(d[1].ToString())) { int proID = Int32.Parse(d[0].ToString().Substring(d[0].ToString().IndexOf('0'), d[0].ToString().Length - d[0].ToString().IndexOf('0'))); cboxSize.Properties.Items.Clear(); cboxSize.Properties.Items.AddRange(preProductSize.getLstSize(proID)); break; } } }