c# - 无法序列化接口(interface) System.Linq.IQueryable

Question

我遇到错误“无法序列化接口(interface) System.Linq.IQueryable”。当我尝试在我的网络服务中运行我的方法时。我的类(class)是这样的:

        public class AirlineSearchStrong
    {
        public Flight_Schedule flightSchedule { get; set; }
        public Flight_Schedule_Seats_and_Price flightScheduleAndPrices { get; set; }
        public Airline airline { get; set; }
        public Travel_Class_Capacity travelClassCapacity { get; set; }

    }

    [WebMethod]
    public IQueryable SearchFlight(string dep_Date, string dep_Airport, string arr_Airport, int no_Of_Seats)
    {        
        AirlineLinqDataContext db = new AirlineLinqDataContext();
        var query = (from fs in db.Flight_Schedules
                     join fssp in db.Flight_Schedule_Seats_and_Prices on fs.flight_number equals fssp.flight_number
                     join al in db.Airlines on fs.airline_code equals al.airline_code
                     join altc in db.Travel_Class_Capacities on al.aircraft_type_code equals altc.aircraft_type_code

                     where fs.departure_date == Convert.ToDateTime(dep_Date)
                     where fs.origin_airport_code == dep_Airport
                     where fs.destination_airport_code == arr_Airport
                     where altc.seat_capacity - fssp.seats_taken >= no_Of_Seats
                     select new AirlineSearchStrong { 
                     flightSchedule = fs,
                     flightScheduleAndPrices = fssp,
                     airline = al,
                     travelClassCapacity = altc
                     });
            return query;


    }

我试过 IQueryable、IList 和 returning .ToList()，但大部分都失败了

Answer 1

我不认为 您可以使用 Iqueryable 或 Ienumerable，因为它们都执行延迟执行并且不可序列化。仅当您遍历集合时才执行查询。因此将查询返回给调用者并要求他在结束时进行迭代是没有意义的。您需要传递 List或 Array .

您可能需要将返回类型更改为 List<Type>