Resolve Castle Windsor dependency by argument name

Question

Given That

Component.For<IService>().ImplementedBy<SecretService>().Named("secretService")
Component.For<IService>().ImplementedBy<PublicService>().Named("publicService")

And

class Foo{
    public Foo(IService publicService){ ...... }
}

And

class Bar{
    public Bar(IService secretService){ ...... }
}

Then how can i achieve the following

Foo and Bar should get instances of publicService and secretService respectively, entirely based on name of their constructor parameters.

So what's your question? Is it not working? What are you seeing instead? What have you tried to get it to work? — Patrick Quirk, Jan 31 '18 at 14:14
Sorry for the confusion, my Question was "how to implement the requirement". by i have now worked it out. Thanks — Gurpreet, Jan 31 '18 at 14:58
Have a look at [Dependency Injection Unity - Conditional Resolving](https://stackoverflow.com/a/32415954/). Note that this answer will work with any DI container, not just Unity. There are additional examples of the strategy pattern [here](https://stackoverflow.com/a/34331154/) and [here](https://stackoverflow.com/a/31971691/). — NightOwl888, Feb 03 '18 at 19:32

score 2 · Accepted Answer · answered Jan 31 '18 at 14:57

I have now made it to work using a custom SubDependencyResolver, i added this to the container and now it injects the implementation by name

public class ByParameterNameResolver : ISubDependencyResolver
{
    private readonly IKernel kernel;

    public ByParameterNameResolver(IKernel kernel)
    {
        this.kernel = kernel;
    }

    public virtual bool CanResolve(CreationContext context, ISubDependencyResolver contextHandlerResolver, ComponentModel model, DependencyModel dependency)
    {
        if (dependency.TargetItemType == null)
            return false;

        if (string.IsNullOrWhiteSpace(dependency.DependencyKey))
            return false;

        return kernel.HasComponent(dependency.DependencyKey);
    }

    public virtual object Resolve(CreationContext context, ISubDependencyResolver contextHandlerResolver, ComponentModel model, DependencyModel dependency)
    {
        return kernel.Resolve(dependency.DependencyKey, dependency.TargetItemType);
    }
}

There might be some ifs and buts that i havn't explored yet. i guess we will find out soon unless you guys can spot something obvious. — Gurpreet, Jan 31 '18 at 15:00

Resolve Castle Windsor dependency by argument name

1 Answers1