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我正在尝试使用 Entity Framework 更新连接表,但我没有走远,因为我收到了一个转换错误:

无法将类型转换为 System.Data.Objects.DataClasses.EntityCollection

因此,当我尝试将乘客对象传递给 Flight 实体时,它无法进行强制转换。

这是表结构:

Flight table - FlightID PK
Passenger Table - Passenger ID PK
Passenger_Flight table - PassengerID PK,FlightID PK


        if (isValid())
        {
            Passenger cpass = ((Passenger)passengerIDComboBox.SelectedItem);

            Flight newflight = new Flight { 

                Rego = planeRegoComboBox.SelectedItem.ToString(),
                DepartureTime = departureDateTimePicker.Value,
                ArrivalTime = arrivalDateTimePicker.Value,
                DepartureLocation = departureLocationComboBox.GetItemText(departureLocationComboBox.SelectedItem),
                ArrivalLocation = arrivalLocationComboBox.GetItemText(arrivalLocationComboBox.SelectedItem),

                Passengers = cpass // this is the problem. Cannot convert type to System.Data.Objects.DataClasses.EntityCollection

        };
            flightEntity.Flights.AddObject(newflight);

            Validate();
            //flightEntity.Passengers.AddObject(pass);
            flightEntity.SaveChanges();
            refreshItems();

        }

提前致谢。我希望我提供了足够的信息。这个问题链接到https://stackoverflow.com/questions/19087747/an-object-with-a-temporary-entitykey-value-cannot-be-attached-to-an-object-cont

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