protected void Button1_Click(object sender, EventArgs e) { if (ddl.SelectedIndex >= 0 && DropDownList1.SelectedIndex >= 0) { localhost.Service serviceObj = new localhost.Service(); values = (List<localhost.Field>)ViewState["listOfValues"]; listOfTables = (List<localhost.Table>)ViewState["listOfTables"]; localhost.Table tableObj = listOfTables[ddl.SelectedIndex]; localhost.Field fieldObj = values[DropDownList1.SelectedIndex]; bool success = serviceObj.DeleteField((int)Session["orgID"], tableObj.ObjIDProperty, fieldObj.FieldIDProperty); if (success) Label1.Visible = true; else Label2.Visible = true; int OrgID = (int)Session["orgID"]; localhost.Table[] array = serviceObj.GetTables(OrgID); listOfTables = new List<localhost.Table>(array); ddl.DataSource = listOfTables; ddl.DataTextField = "TNameProperty"; ddl.DataValueField = "ObjIDProperty"; ddl.SelectedIndexChanged += new EventHandler(ddl_SelectedIndexChanged); ddl.DataBind(); ViewState["listOfTables"] = listOfTables; values = null; DropDownList1.DataSource = null; DropDownList1.DataBind(); } }