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copied!<p>Containers should not have knowledge of their components or how they behave. A container's responsibilities are typically the domain of instantiation dependency - not communication dependency. A container should be a generalized factory.</p> <p>This is the reason why structural graph != communication graph. As I am sure you have realized, as a factory a container is the root of your object graph, but a container responding to or publishing an event simply does not make sense.</p> <p>What you want then, is someone who's job it is to manage events. A specialized component that knows <em>about</em> events, and can <em>broker</em> an instance of one to interested parties. You want a generalized event broker. An event router if you will.</p> <p>You could probably find many implementations of one. Such as Cab's EventBroker, Prism's event aggregator, or my favourite <a href="http://kentb.blogspot.com/2008/03/event-hub.html" rel="nofollow noreferrer">EventHub</a>. This last one is a culmination of experience from working with Cab extensively and correspondence with Jeremy Miller and Glenn Block, by <a href="https://stackoverflow.com/users/5380/kent-boogaart">Kent, a very cool guy</a>.</p> <p>If you are using a container, you are likely familiar with Dependency Injection and Inversion of Control. Someone who needs to publish events is injected an IEventHub and invokes Publish with a strongly typed subject class. Someone who needs to subscribe to an event is also injected an IEventHub and implements a strongly typed ISubscriber interface [which basically exposes a strongly typed Receive method]. That's it.</p> <p>Now events can travel any which way [as business requirements permit], as they should.</p>

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