Catel offers lots of out-of-the-box services and implementations. Services can be used to separate the logic of external functionality in a service. The advantages of this technique are:
- Separation of Concerns
- Unit testing (mocking interfaces is easy)
All services provided by Catel have both a unit test version and a real (or production version). For example, the IMessageService has a test implementation that does not show a message box, but checks the result only.