LINQ C# include nested entities

Question

I got following structure:

Class A has a member: List<ClassB>

Class B has a member: List<ClassC>

Who is it possible to get for one specific object of class A one specific object of List<B> and all of it's objects in List<ClassC>?

In a other way: How can I get the List<ClassC> for a specific ClassB?

Possible duplicate of [Difference Between Select and SelectMany](http://stackoverflow.com/questions/958949/difference-between-select-and-selectmany) — GSerg, Apr 05 '17 at 17:50
Are you using EF and are those classes entities of your model? How do you know which `ClassB` object you want to get? — ocuenca, Apr 05 '17 at 17:51

score 1 · Answer 1 · edited Apr 05 '17 at 17:54

1

Try:

var a_list = new List<A>();
var c_list = a_list.First(a => [your criteria here])
                   .b_list
                   .First(b => [your criteria here])
                   .c_list;

edited Apr 05 '17 at 17:54

msitt

1,237
12
27

answered Apr 05 '17 at 17:51

stelioslogothetis

9,371
3
28
53

Ranjith V · Answer 2 · 2017-04-05T18:23:08.770

0

You can try ( to avoid any exceptions)

 ClassA classAItem = yourClassAList.FirstOrDefault({your A condition})

    if(classAItem != null)
    {
      ClassB  classBItem = classAItem.yourClassBList.FirstOrDefault({your B condition});

      if(classBItem != null)
      {
        List<ClassC> classCItem = classBItem.yourClassCList);
      }
}

edited Apr 05 '17 at 18:23

answered Apr 05 '17 at 17:59

Ranjith V

298
1
3
16

score 0 · Accepted Answer · answered Apr 06 '17 at 08:15

0

Found the solution:

_db.ClassA.Include(b => b.ClassB).ThenInclude(c => c.ClassC);

Thanks for your answers!

answered Apr 06 '17 at 08:15

sampa

535
4
27

LINQ C# include nested entities

3 Answers3