EF Linq包含嵌套数组

Question

I have 3 classes in EF-Code-First

public class User {
    public string Id { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public virtual ICollection<Flat> Flats { get; set; }
}

public class Flat {
    public string Id { get; set; }
    public string Number { get; set; }
    public virtual House House { get; set; }
    public virtual ICollection<User> Users { get; set; }
}

public class House {
    public string Id { get; set; }
    public string Street { get; set; }
    public string Number { get; set; }
    public virtual ICollection<Flat> Flats { get; set; }
}

And I want to get all users.

I do:

var Result = _storage.Users
    .Include(x => x.Flats)
    .Include(y => y.Flats.Select(z => z.House))
    .ToList();

And in Result I have Users with Flats , but Flats don't have their Houses .

What am I doing wrong?

Answer 1

You only need to add one include, the one to the deepest level:

var Result = _storage.Users
.Include(user => user.Flats.Select(flat => flat.Houses))
.ToList();

This will automatically include all Houses properties as well as all Flat properties and the Houses properties

Other Flat Collections will not be included. For those you would need an extra Include.