Using AutoFac without constructor injection

Question

I am trying to use AutoFac and all the examples show it using constructor injection which is a suggested practice. That's ok, but I want to know how to use it where constructor injection is not possible. For example, I want to use NLogger in my app.

Registration happens like so:

builder.RegisterType<NLogger>().As<ILogger>().SingleInstance();

How would I use NLogger without doing like this:

public class ProductService : IProductService
{
    private ILogger _logger;
    public ProductService(ILogger logger)
    {
        this._logger = logger;
    }
 }

Any help is greatly appreciated.

Regards.

Answer 1

You can use Property Injection.

In your class you can have

public class MyClass
{
    public ILogger Logger { get; set; }
}

and map with

builder.Register(c => new MyClass { Logger = c.Resolve<ILogger>() });

Constructor injection is the way to go in 99% of cases though.

---

If you just want to get an instance you need to call

var logger = container.Resolve<ILogger>();

Where container is your AutoFac container - this could be pulled from a global variable - in ASP.NET MVC (if you happen to be using that) you can do this by calling

var logger = DependencyResolver.Current.GetService<ILogger>();