Question

I have a dependency being injected via Func<Owned<OwnedDependency>>. One of its dependencies requires a parameter that I will only have at the point of constructing OwnedDependency.

public class OwnedDependency
{
    public OwnedDependency(IDependency1 dependency)
    {
    }
}

public interface IDependency1
{
}

public class Dependency1 : IDependency1
{
    public Dependency1(MyParameter parameter)
    {
    }
}

public class MyClass
{
    private readonly Func<Owned<OwnedDependency>> m_ownedDependencyFactory;

    public MyClass(Func<Owned<OwnedDependency>> ownedDependencyFactory)
    {
        m_ownedDependencyFactory = ownedDependencyFactory;
    }

    public void CreateOwnedDependency()
    {
        var parameter = new MyParameter(...);
        // ** how to setup parameter with the container? **

        using (var ownedDependency = m_ownedDependencyFactory())
        {
        }
    }
}

I can’t work out a clean way of setting up the instance of MyParameter.

One approach I have explored is to inject ILifetimeScope into MyClass and then do something like:

var parameter = new MyParameter(...);

using (var newScope = m_lifetimeScope.BeginLifetimeScope())
{
    newScope.Resolve<IDependency1>(new TypedParameter(typeof(MyParameter), parameter));
    var ownedDependency = newScope.Resolve<OwnedDependency>();
    // ...
}

but the container is becoming unnecessarily intrusive. Ideally what I would like to do is inject Func<IDependency1, Owned<OwnedDependency>> and the container be willing to use parameters passed in to satisfy any necessary dependency, not just the ones on OwnedDependency.

Answer 1

What about doing the resolution in two steps with using another factory for IDependency1:

public class MyClass
{
    private Func<MyParameter, IDependency1> dependency1Factory;
    private Func<IDependency1, Owned<OwnedDependency>> ownedDependencyFactory;


    public MyClass(
        Func<MyParameter, IDependency1> dependency1Factory,
        Func<IDependency1, Owned<OwnedDependency>> ownedDependencyFactory)
    {
        this.dependency1Factory = dependency1Factory;
        this.ownedDependencyFactory = ownedDependencyFactory;
    }

    public void CreateOwnedDependency()
    {
        var parameter = new MyParameter();
        using (var owned = ownedDependencyFactory(dependency1Factory(parameter)))
        {
        }

    }
}