Inject different object to constructor with StructureMap for certain case

Question

I have IRepository<T> , and implementation SqlRepository<T>. SqlRepository has DataContext parameter in constructor.

SM configuration looks like this:

x.ForRequestedType(typeof(IRepository<>))
.TheDefaultIsConcreteType(typeof(SqlRepository<>));

x.ForRequestedType<DataContext>().CacheBy(InstanceScope.Hybrid)
.TheDefault.Is.ConstructedBy(()=>{
                        var dc = new FirstDataContext();
                        dc.Log = new DebuggerWriter();
                        return dc;
                    });

But for construction of IRepository<SpecificObject> i want to inject different DataContext. How do I say SM that when I ask for IReposiotry<SpecificObject> I want different DataContext, not FirstDataContext but SecondDataContext (that DC goes to different database).

For example, when I ask for IRepository<T> I want FirstDataContext to be injected, but when I ask explicity for IRepository<Product> I want SecondDataContext to be injected.

Also, that SecondDC should be Hybrid cached by SM!

Answer 1

Something like...

ForRequestedType<DataContext>()
    .CacheBy(InstanceScope.Hybrid)
    .AddInstances(inst => inst.ConstructedBy(() => 
        new SecondDataContext { Log = new DebuggerWriter() })
        .WithName("secondDataContext"))
    .TheDefault.Is
    .ConstructedBy(() => new FirstDataContext {Log = new DebuggerWriter()});

ForRequestedType<IRepository<SpecificObject>>()
    .TheDefault.Is
    .OfConcreteType<SqlRepository<SpecificObject>>()
    .CtorDependency<DataContext>()
    .Is(inst => inst.TheInstanceNamed("secondDataContext"));

Answer 2

That really helped me too. Have a concrete class used in a constructor that in turn gets a different connection string in its constructor depending on which "parent" class is using it. Thanks.

            ObjectFactory.Initialize(x=>
                                     {
                                         // Different connection string for each usage
                                         // of the RelationalGateway class
                                         x.ForRequestedType<RelationalGateway>()
                                             .AddInstances(r =>
                                                 r.ConstructedBy(() => 
                                                     new RelationalGateway(ConfigRepository.DataSourceName))
                                             .WithName("config"))
                                             .TheDefault.Is.ConstructedBy(
                                             () => new RelationalGateway(OracleSpatialRepository.DataSourceName));

                                         // Inject the right RelationalGateway
                                         x.ForRequestedType<IConfigRepository>()
                                             .TheDefault.Is.OfConcreteType<ConfigRepository>()
                                             .CtorDependency<RelationalGateway>().Is(inst => 
                                                 inst.TheInstanceNamed("config"));

                                         x.ForRequestedType<ISpatialRepository>()
                                             .TheDefault.Is.OfConcreteType<OracleSpatialRepository>()
                                             .CtorDependency<RelationalGateway>().IsTheDefault();

                                         // Other simple types
                                         x.ForRequestedType<IIdGenerator>().TheDefaultIsConcreteType<IdGenerator>();
                                     });