Autofac with multiple implementations of the same interface

Question

I\'m using Autofac and would like to have multiple implementations of an interface. How can I configure Autofac so to resolve dependencies based on the current type?

Mor

Answer 1

For anyone else searching, I just ran across this. You can use implicit support for the IEnumerable. I wrote it up for future use.

Basically, you can register assembly types by name (or other criteria) as an IEnumerable which can be consumed later. My favorite part of this approach is that you can keep adding message handlers and as long as you stick to the same criteria, you never have to touch the criteria afterwards.

Autofac Registration:

builder.RegisterAssemblyTypes(typeof (LoggingMessageHandler).Assembly)
  .Where(x => x.Name.EndsWith("MessageHandler"))
  .AsImplementedInterfaces();

Consuming Class:

public class Foo
{
  private readonly IEnumerable _messageHandlers

  public Foo(IEnumerable messageHandlers)
  {
    _messageHandlers = messageHandlers;
  }

  public void Bar(message)
  {
    foreach(var handler in _messageHandlers)
    {
      handler.Handle(message)
    }
  }
}