Difference between standard ninject and ninject.web.mvc in an MVC3 project?

Question

I understand some of the functionality of Ninject and have been able to use it for IoC.

When I go to add a reference to Ninject to a project in VS2010, using NuGet, I see other Ninject extensions in the list. Specifically Ninject.MVC3. Also on the Ninject website under extensions ( http://www.ninject.org/extensions.html ) I see Ninject.Web.Mvc.

If I am creating MVC3 applications do I need to use this extension of Ninject? Does my basic use of Ninject for IoC with classes/interfaces require anything beyond the standard library?

What is the difference between Ninject and Ninject.MVC3/Ninject.Web.Mvc in an MVC3 project?

Answer 1

ninject.web.mvc is a ninject (core) complement for the ASP MVC (3) applications. Basically - you should use it, when you want to use Ninject in an ASP MVC project.

From the documentation:

This extension allows integration between the Ninject core and ASP.NET MVC projects. To use it, just make your HttpApplication (typically in Global.asax.cs) extend NinjectHttpApplication:

MVC 3 extension contains the crucial methods to wire up the DI composition root into MVC application - it means that Ninject will be responsible for instantiating your controllers, that has dependencies on other components (Ninjects 'overrides' the use of DefaultControllerFactory which is only able to create controllers with parameterless constructors).

In the documentation there are mentioned two methods, how to do it: either extending the NinjectHttpApliaction in global.asax or using the NinjectWebCommon class inside the App_Start folder.

There is also ninject.web.common extension, which is required for ninject.web.mvc. It contains e.g. the definition of InRequestScope.