public FileContentResult ListaArticulosExcel()
        {
            if (Session[_session_lista_articulos] == null)
            {
                List <Ent_Orce_Inter_Art> liststoreConf = new List <Ent_Orce_Inter_Art>();
                Session[_session_lista_articulos] = liststoreConf;
            }
            List <Ent_Orce_Inter_Art> lista = (List <Ent_Orce_Inter_Art>)Session[_session_lista_articulos];

            string[] columns     = { "ARTICULO", "VALOR" };
            byte[]   filecontent = ExcelExportHelper.ExportExcel3(lista, "", false, columns);
            string   nom_excel   = "Lista de Articulos";

            if (lista.Count > 0)
            {
                nom_excel = lista.First().ATRIBUTO;
            }
            return(File(filecontent, ExcelExportHelper.ExcelContentType, nom_excel + ".xlsx"));
        }