How to Pass Constructor Parameters to Unity's Resolve() Method

Can I pass constructor parameters to Unity's Resolve() method?

As of today they have added this functionality:

It’s in the latest drop here:

http://unity.codeplex.com/SourceControl/changeset/view/33899

Discussion on it here:

http://unity.codeplex.com/Thread/View.aspx?ThreadId=66434

Example:

container.Resolve<IFoo>(new ParameterOverrides<Foo> { { "name", "bar" }, { "address", 42 } });"

configure Unity to resolve a constructor parameter and interface

var container = new UnityContainer();
var phone = "214-123-4567";
container.RegisterType<IFaxProvider, EFaxProvider>();
container.RegisterType<IFaxService, FaxService>(new InjectionConstructor(phone, typeof(IFaxProvider)));

var fax = container.Resolve<IFaxService>();

How resolve a dependency with unity passing arguments in the constructor?

Create an InjectionConstructor and pass that to RegisterType():

var unityContainer = new UnityContainer();

ISnuh snuh = new Snuh();
InjectionConstructor injectionConstructor = new InjectionConstructor(snuh);

unityContainer.RegisterType<ICalculator, SimpleCalculator>(injectionConstructor);

If you have to do it only when you resolve the type, that's when ResolverOverride[] would be used:

public static T Resolve<T>(this IUnityContainer container, params ResolverOverride[] overrides);

Per MSDN:

Use ParameterOverride to override the specified constructor parameter
or parameters.

Unity – Resolving objects by passing constructor parameter

You should register Parent1 with dependency to Document in constructor:

    Container.RegisterType<IParent, Parent1>("Parent1", new InjectionConstructor(doc));

then you can resolve an instance of that class:

        string parentClass = "Parent1";
        IParent parent = Container.Resolve<IParent>(parentClass);

How to send a parameter to an object's constructor with Unity's Resolve() method?

Here's a related question that answers this pretty well:
Can I pass constructor parameters to Unity's Resolve() method?

The only option you have if you want to do this is a scoped container.

IUnityContainer subContainer = this.container.CreateScopedContainer();
subContainer.RegisterInstance<Customer>(customer);
smartFormPresenter1 = subContainer.Resolve<SmartFormPresenter>();

How to pass a type as parameter to a constructor when using Unity dependency injection

The answer was contained in the code from the link posted by Haukinger:

object actual = 
    container.Resolve<IDatarecordSerializer>(
        new ParameterOverride(
            "type", 
             new InjectionParameter(typeof(string))
        )
    );

How to pass runtime value to constructor parameter when register a type?

Within the InjectionFactory method, use a Resolve method overload that allows you to specify a ResolverOverride, specifically a ParameterOverride, and pass the runtime value in that way. To avoid a StackOverflowException, you can use an additional named registration with compile-time values provided for the relevant parameters, like this:

class A
{
    public A(int id, B b, C c)
    {
        Trace.WriteLine("Got " + id);
    }
}

class B { }

class C { }

static void Main(string[] args)
{
    using (var unity = new UnityContainer())
    {
        unity.RegisterType<A>(
            "compile-time", 
            new InjectionConstructor(-1, 
                new ResolvedParameter<B>(), 
                new ResolvedParameter<C>()
                )
        );
        unity.RegisterType<A>(
            new InjectionFactory(
            u => u.Resolve<A>("compile-time", 
                new ParameterOverride("id", new Random().Next()))
            )
        );
        unity.Resolve<A>();
        unity.Resolve<A>();
        unity.Resolve<A>();
    }
}

Resolve with parameter from other constructor with unity

I register all my types at service startup, but at startup i do not
know the "customerName"-parameter

In other words, your customerName parameter is runtime data. Injecting runtime data into components during the components' initialization is an anti-pattern.

There are two possible solutions to your problem, but in your your case, the most likely solution is to pass through the parameter through the public API as follows:

public class Service
{
    private readonly IManager _manager;

    public Service(IManager manager) {
        _manager = manager;
    }

    public void ServiceCall(string customerName) {
        _manager.DoSomething(customerName);
    }
}

Here the IManager interface is changed so that the customerName is passed through the DoSomething method. Because the runtime value isn't needed anymore during construction, there is no need to inject the Unity container into the Service (which is a form of the Service Locator anti-pattern).

For the second option, please read this article.

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