c# - 具有两个在 EF 6 中工作的联接的 LINQ 查询在 EF 7 中给出错误

Question

我有一个在 EF 6(代码优先)项目中工作的 LINQ 查询。现在我已将代码迁移到 EF 7，此查询现在引发异常:ArgumentException:未为类型“X.Models.Domain.MadeChoice”定义属性“Int32 ID”

查询:

var madeChoices = from res in X.Instance.Residence
                  join room in X.Instance.Room on res.ID equals room.Residence.ID
                  join madeChoice in X.Instance.MadeChoice on room.ID equals madeChoice.Room.ID
                  where res.ID == residence.ID
                  select room.MadeChoices;

MadeChoice 类:

public class MadeChoice
{
    public virtual int ID { get; set; }

    [Required]
    public virtual ChoiceGroup Choicegroup { get; set; }

    [Required]
    public virtual Room Room { get; set; }

    [Required]
    public virtual Item Item { get; set; }
}

房间类:

public class Room
{
    public virtual int ID { get; set; }
    public string Name { get; set; }
    public string Description { get; set; }

    public virtual Residence Residence { get; set; }
    public virtual RoomType RoomType { get; set; }
    public virtual List<MadeChoice> MadeChoices { get; set; }

    // Constructors:
    public Room()
    {
        this.MadeChoices = new List<MadeChoice>();
    }
}

住宅类:

public class Residence
{
    public int ID { get; set; }
    public string ApartmentNumber { get; set; }

    public static IQueryable<List<MadeChoice>> GetMadeChoices(Residence residence)
    {
        var madeChoices = from res in X.Instance.Residence
                            join room in X.Instance.Room on res.ID equals room.Residence.ID
                            join madeChoice in X.Instance.MadeChoice on room.ID equals madeChoice.Room.ID
                            where res.ID == residence.ID
                            select room.MadeChoices;
        System.Diagnostics.Debug.Write("MadeChoices.Count: ");
        System.Diagnostics.Debug.WriteLine(madeChoices.Count());
        foreach (var madechoice in madeChoices)
        {
            System.Diagnostics.Debug.Write("MadeChoice.Count: ");
            System.Diagnostics.Debug.WriteLine(madechoice.Count());
        }
        return madeChoices;
    }

    // Navigational properties:
    public virtual List<Room> Rooms { get; set; }
    public virtual ResidenceType ResidenceType { get; set; }
    public virtual List<Tenant> Tenants { get; set; }
    public virtual List<PeriodResidenceDeadline> PeriodResidenceDeadline { get; set; }

    // Constructors:
    public Residence()
    {
        this.Rooms = new List<Room>();
        this.Tenants = new List<Tenant>();
        this.PeriodResidenceDeadline = new List<PeriodResidenceDeadline>();
    }
}

本来ID不是virtual但是不影响报错。数据库看起来与 EF 6 中的一样。关系是一对多的。我使用 EF 7.0.0-rc1-final。

有什么提示吗？

提前致谢

彼得

Answer 1

正如 EF 团队所说，EF Core RC1 不处理复杂的子类型(请在此处查看他们的路线图 https://github.com/aspnet/EntityFramework/wiki/Roadmap#in-progress 查询)

对于查询，这将在 EF Core 1.0 RTM 版本中处理。

同时，您可以使用我在这里列举的解决方案之一:EF Core fluent mapping to inner object properties (映射的问题是一样的)