Get an instance of an object with Ninject

ridermansb picture ridermansb · Oct 10, 2011 · Viewed 14.6k times · Source

I installed on my project Ninject.MVC3 via Nuget.

I read this article that to inject dependencies in my controllers, all you had to do was install Ninject, add my dependencies in NinjectMVC3.cs and ready.

So far so good, but how to retrieve the instance of an object?

public ActionResult MyAction()
{
    var myObject = /* HERE  ??*/
}

In the constructor of the controller I have no problems!

public class AccountController : Controller
{
    public AccountController(IRepository repository) { ... } //This works!!
}

Answer

Buildstarted picture Buildstarted · Oct 10, 2011

The reason it works is because the ControllerFactory looks for DI and automatically adds it. If you want to get a specific instance you can do this:

private static void RegisterServices(IKernel kernel) {
    kernel.Bind<ICoolObject>().To(CoolObject);
}

public ActionResult MyAction() {
    var myObject = 
        System.Web.Mvc.DependencyResolver.Current.GetService(typeof (ICoolObject));
}

Becareful though. This is done quite often with those new to Dependency Injection (myself included). The question is why do you need to do it this way?