How to register a disposable Concrete type in Simple Injector container

Question

I found the following code at Simple Injector Website

public static void RegisterDisposableTransient<TService, TImplementation>(
    this Container container)
    where TImplementation : class, IDisposable, TService
    where TService : class
{
    var scoped = Lifestyle.Scoped;
    var reg = Lifestyle.Transient.CreateRegistration<TService, TImplementation>(
        container);

    reg.SuppressDiagnosticWarning(DiagnosticType.DisposableTransientComponent, 
            "suppressed.");

    container.AddRegistration(typeof(TService), reg);
    container.RegisterInitializer<TImplementation>(
        o => scoped.RegisterForDisposal(container, o));
}

I want to register a concrete implementation (one that does not implement any particular interface) that is Disposable for the transient scope. What changes do I need to make to the code above

Answer 1

In case you want to register a concrete disposable type, typically the simplest (and best) thing to do is to register it as Scoped:

container.Register<MyConcrete>(Lifestyle.Scoped);

In case you really need that instance to be transient (unlikely), you will have to do the following.

It's just a matter of using the CreateRegistration<TConcrete> overload:

public static void RegisterDisposableTransient<TConcrete>(this Container container)
    where TConcrete : class, IDisposable
{
    var scoped = Lifestyle.Scoped;
    var reg = Lifestyle.Transient.CreateRegistration<TConcrete>(container);

    reg.SuppressDiagnosticWarning(DiagnosticType.DisposableTransientComponent, "suppres");

    container.AddRegistration(typeof(TConcrete), reg);
    container.RegisterInitializer<TConcrete>(
        o => scoped.RegisterForDisposal(container, o));
}