public JsonResult LastIndex()
        {
            int id = FacturasBLL.Identity();

            if (id > 1 || FacturasBLL.Listar().Count > 0)
            {
                ++id;
            }
            return(Json(id));
        }
        public JsonResult BuscarVentas(int facturaId)
        {
            var factura = FacturasBLL.Listar();

            return(Json(factura));
        }
 public ActionResult Index()
 {
     return(View(FacturasBLL.Listar()));
 }