Question

There seem to be many ways to apply the repository patterns that is why i need your opinion and a good clear answer on what seem the best way of applying the repository pattern. It is the generic repository ? But there is a problem where some domain object dont have the same behaviour as others. It is specify repository ? What about code repeatition between repositories? it is both combinaison ? how about using a di container for both kind of implementation ?

Thanks

Edit: the orm i am using is entity framework 4. Would be nice to have an example with EF4.

Answer 1

This post by Gabriel Schenker is a good explanation of the repository pattern. He implements it with NHibernate (you don’t say which ORM you are using) and provides a generic base repository. For me the repository pattern is very connected to testing and being able to fake it or mock it and this blog post also shows how to make your own fake.

In my experience most repositories share some common functionality e.g. GetById, Add, Remove. So it is useful to have a base class that can be inherited. Where it can get a little trickier is when you start thinking about dynamic Linq queries and how those can be tested.

Examples of repository patterns with Linq can be found here and here but I would start simple as these could be overkill for some projects.