using System;

using System.Linq;

using DryIoc;

public class Program

{

    public static void Main()

    {

        var container = new Container();

​

        container.Register<LeafOne>(Reuse.Singleton);

        container.Register<LeafTwo>(Reuse.Singleton);

        // the keys are required in the DryIoc <=4.3.4 because RegisterMapping uses the IfAlreadyRegistered.Keep by default,

        // keeping the first Base registration and rejecting the second

        //container.RegisterMapping<Base, LeafOne>(serviceKey: 1); 

        //container.RegisterMapping<Base, LeafTwo>(serviceKey: 2);

        // Works too        

        //container.RegisterDelegate<Base>(r => r.Resolve<LeafOne>());

        //container.RegisterDelegate<Base>(r => r.Resolve<LeafTwo>());

​

        // Works too - ant it is more preferable because it won't use the service locator internal Resolve call

        //container.RegisterDelegate<LeafOne, Base>(x => x);

        //container.RegisterDelegate<LeafTwo, Base>(x => x);

​

        var bases = container.ResolveMany<Base>().ToArray();

        Console.WriteLine(bases.Length);

    }

    abstract class Base {};

    class LeafOne : Base {};

    class LeafTwo : Base {};

}