Autofac different service resolution based on TypedParameter

Question

Is there anyway to get autofac to resolve the service that has a concrete implementation with the constructor that matches a given parameter most specifically.

By this i mean match a constructor for a child type instead of matching the constructor for the base type.

For example i'd like to make the following test pass

[TestFixture]
public class AutofacResolvTestFixture
{
    [Test]
    public void test()
    {
        var cb = new ContainerBuilder();
        cb.RegisterType<Child1>();
        cb.RegisterType<Child2>();
        cb.RegisterType<ServiceImpl1>().As<IService>();
        cb.RegisterType<ServiceImpl2>().As<IService>();
        var container = cb.Build();
        var c1=container.Resolve<Child1>();
        var c2=container.Resolve<Child2>();
        var s1 = container.Resolve<IService>(new TypedParameter(c1.GetType(), c1));
        var s2 = container.Resolve<IService>(new TypedParameter(c2.GetType(), c2));
        Assert.That(s1, Is.InstanceOf<ServiceImpl1>());
        Assert.That(s2, Is.InstanceOf<ServiceImpl2>());
        Assert.That(s1.ConstructorParam, Is.SameAs(c1));
        Assert.That(s2.ConstructorParam, Is.SameAs(c2));
    }
}

public class baseClass {}
public class Child1 : baseClass{}
public class Child2 : baseClass{}

public interface IService
{
    baseClass ConstructorParam { get; }
}

public class ServiceImpl1 : IService
{
    private baseClass _b;
    public ServiceImpl1(baseClass b)
    {
        _b = b;
    }

    public baseClass ConstructorParam
    {
        get
        {
            return _b;
        }
    }
}


public class ServiceImpl2 : IService
{
    private baseClass _b;
    public ServiceImpl2(Child2 b)
    {
        _b = b;
    }

    public baseClass ConstructorParam
    {
        get
        {
            return _b;
        }
    }
}

My goal is to make IService, IEditor and be able to resolve the IEditor for a type by passing it to autofac. I want to do this so that i can "override" the editor for a type by simply inheriting IEditor and using the appropriate constructor type that that IEditor is for.

Thank you.

Answer 1

Take a look at my solution to this question. Perhaps you can use the same solution, with a Func<Type, IService> factory delegate instead, and have ServiceImplX Keyed to the corresponding child type instead of using Named registrations.