Get child from inherit class

Question

I have 2 classes

public class A
{
    public string prop1 { get; set; }
    public string prop2 { get; set; }
    public string prop3 { get; set; }
}

public class B : A
{
    public string prop4 { get; set; }
}

And I have a method to fill a List with type B.

Question: What is the easiest way to get the result into List<A>

List<B> BList = new List<B>();
BList = GetData(); //fill List with Data
List<A> AList = (List<A>)BList; // convert? cast?

Class A has all fields of Class B so there must be a easy way to get from B to A.

Since you have a `List` here, you could also use Linq projection `List AList = BList.Select(b => (A)b).ToList();` — , Sep 21 '16 at 06:27

score 2 · Accepted Answer · answered Sep 21 '16 at 06:19

2

You can use a Linq function:

List<A> AList = BList.Cast<A>().ToList();

answered Sep 21 '16 at 06:19

Fratyx

5,717
1
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22

score 1 · Answer 2 · answered Sep 21 '16 at 06:19

1

You will have to create a new List<A> instance with references to all the items from BList:

List<A> AList = new List<A>(BList);

That's because List<T> is not covariant (and can't be).

answered Sep 21 '16 at 06:19

MarcinJuraszek

124,003
15
196
263

Thank you both for answering. – c0rd Sep 21 '16 at 06:31

Get child from inherit class

2 Answers2