实体框架Mysql嵌套属性

Question

i have this class structure. When i do some select i get an exception error.

public class A
{
    public int AId { get; set; }
    public virtual ICollection<B> B { get; set; }
}

public class B
{
    public int BId { get; set; }
    public virtual C C { get; set; }

    public int AId { get; set; }
    public virtual A A { get; set; }
}

public class C // Manifiesto carga
{
    [Key]
    [ForeignKey("B")]
    public int CId { get; set; }

    public virtual B B { get; set; }
    public virtual ICollection<D> D { get; set; }
    public virtual ICollection<E> E { get; set; }
}

public class D
{
    public int DId { get; set; }
    public string Nombre { get; set; }

    public int CId { get; set; }
    public virtual C C { get; set; }
}

public class E
{
    public int EId { get; set; }
    public string Nombre { get; set; }

    public int CId { get; set; }
    public virtual C C { get; set; }
}


    context.AA
                .Include(e => e.B.Select(s => s.C.D))
                .Include(e => e.B.Select(s => s.C.E)).FirstOrDefault(e => e.AId == 1);

Im lost, what can i do? or where im failing?

Thank you.

(sorry for my english)

Image exception

In the picture above you can see the exception message.

Answer 1

Is the problem fixed when you also put the parent in D and E

public class D {
   public virtual C C {get;set;}
}
public class E {
   public virtual C C {get;set;}
}