Question

I can resolve generic interfaces to generic classes like the common generic repository pattern.

IRepository<objectA> resolves to Repository<objectA>
IRepository<objectB> resolves to Repository<objectB>

But then for objectC I need a concrete Repository, namely ObjectCRepository that extends Repository<objectC>. If I register this won’t there be two different registrations for for IRepository<objectC> and everything fails?

Answer 1

There will be two registrations, but they don’t conflict. Unity is smart enough to prefer fully defined closed generics over open ones. For example this works fine:

<unity xmlns="http://schemas.microsoft.com/practices/2010/unity">
    <alias alias="ILog_Interface" type="Common.ILog`1, Common2"/>
    <alias alias="Logger_Class" type="Common.Logger`1, Common2"/>
    <alias alias="DemoServiceLog_Interface" type="Common.ILog`1[[Services.Demo.DemoService, Services.Demo]], Common2"/>
    <alias alias="DemoServiceLog_Class" type="Common.ServiceLogger`1[[Services.Demo.DemoService, Services.Demo]], Common2"/>

        <container name="DemoService">
          <register type="ILog_Interface" mapTo="Logger_Class"/>
          <register type="DemoServiceLog_Interface" mapTo="DemoServiceLog_Class"/>
        </container>
</unity>