Ninject contextual bindinng like structuremap

Question

Hi I am using Ninject IoC container. I can not convert the structuremap code to ninject.

This is Structuremap code binding

For<IProductCatalogService>().Use<ProductCatalogService>().Named("realProductCatalogService");
For<IProductCatalogService>().Use<CachedProductCatalogService>()
                  .Ctor<IProductCatalogService>().Is(p => p.TheInstanceNamed("realProductCatalogService"));

And I am using Ninject code like this

Kernel.Bind<IProductCatalogService>().To<ProductCatalogService>().Named("realProductCatalogService");
Kernel.Bind<IProductCatalogService>().To<CachedProductCatalogService>().Named("cachedProductCatalogService");

But this not working.

Answer 1

I suggest you want to inject some implementation of IProductCatalogService into CachedProductCatalogService, that also implements IProductCatalogService and then use this cached implementation in the rest of the application as the default component.

With Ninject you can configure it using the .WhenParentNamed conditional binding like this:

Kernel.Bind<IProductCatalogService>()
      .To<ProductCatalogService>()
      .WhenParentNamed("cached");

Kernel.Bind<IProductCatalogService>()
      .To<CachedProductCatalogService>()
      .Named("cached");

When there is a request for IProductCatalogService ninject will try to resolve the conditions. If the parent component (that asked for the injection) is named "cached" (the CachedProductCatalogService in your case) than ninject will return ProductCatalogService otherwise it will return CachedProductCatalogService as the default.