using System;

using Autofac;

using Autofac.Features.AttributeFilters;

​

public class Program

{

    public interface IHello

    {

         string Greetings { get; }

    }

    public class Hello : IHello

    {

        public string Greetings

        {

            get;

            set;

        }

    }

    public class HelloConsumer

    {

        public HelloConsumer([KeyFilter("EN")] IHello hello)

        {

            Console.WriteLine(hello.Greetings);

        }

    }

​

    public static void Main()

    {

        ContainerBuilder cb = new ContainerBuilder();

        cb.RegisterType<HelloConsumer>().AsSelf().WithAttributeFiltering();

        var helloEn = new Hello { Greetings = "Hi" };

        var helloFr = new Hello { Greetings = "Bonjour" };

        cb.Register<Hello>(x => helloEn).Keyed<IHello>("EN");

        cb.Register<Hello>(x => helloFr).Keyed<IHello>("FR");

        var container = cb.Build();

        container.Resolve<HelloConsumer>(); // Should write the correct greeting

    }

}