public void bind_state() { try { bl.Category = ddl_country.SelectedValue; dtt = dl.bind_state(bl); ddl_state.Items.Clear(); ddl_state.DataSource = dtt.table; ddl_state.DataTextField = "Name"; ddl_state.DataValueField = "Id"; ddl_state.DataBind(); ddl_state.Items.Insert(0, new ListItem("Select State", "0")); } catch (NullReferenceException) { // Utilities.MessageBox_UpdatePanel_Redirect(UpdatePanel2, "Your Session Has Expired Please Login Again", "../Logout.aspx"); } }