Question

I can’t figure out how to do following with UnityContainer.

interface A { }
interface B { }
interface X { }
class ConcreteAX : A, X { }
class ConcreteBX : B, X { }

I need to register both concrete classes so as ServiceLocator.ResolveAll<X> should return both instances. Same time Resolve<A> and Resolve<B> should work as well. Moreover, I must not instantiate them myself while registering services.

If I use named registration for X to make ResolveAll work, then two instances of each of concrete classes are created. If I use named registration for all interfaces, then Resolve<A> and Resolve<B> does not work. If I use this approach then ResolveAll returns nothing.

How to do the trick with UnityContainer?

Answer 1

Do the second (named) registration using ExternallyControlledLifetimeManager and InjectionFactory in which you resolve the default registration. For example:

unity.RegisterType<A, ConcreteAX>(new ContainerControlledLifetimeManager());
unity.RegisterType<B, ConcreteBX>(new ContainerControlledLifetimeManager());
unity.RegisterType<X, ConcreteAX>("AX", 
    new ExternallyControlledLifetimeManager(), 
    new InjectionFactory(u => u.Resolve<A>()));
unity.RegisterType<X, ConcreteBX>("BX", 
    new ExternallyControlledLifetimeManager(), 
    new InjectionFactory(u => u.Resolve<B>()));