Register a custom model binder in MVC 4

Question

In MVC 3, I created custom model binders by creating a new class that implemented `Systen.Web.Mvc.IModelBinder`, and then registered it inside `Global.asax.cs` and inside `Application_Start()` using `ModelBinders.Binders.Add(typeof(sometype), new MyModelBinder());` In MVC 4 I understand that you are supposed to use `System.Web.Http.ModelBinding.IModelBinder` to implement model binders. So I have two questions: Why are we supposed to use the model binder from `System.Web.Http.ModelBinding` instead of the one from `Systen.Web.Mvc`? I don't see it is listed as deprecated anywhere, so what is the problem with the old one? If I implement my model binder from the `System.Web.Http.ModelBinding.IModelBinder`, how do I register it inside my application so it will actually be used?

Accepted Answer

You can register your model binder in the same way(in the Global.asax.cs) and you can also use the `System.Web.Mvc.IModelBinder` interface.

However, the System.Web.Http namespace is basically for the ASP.NET MVC Web API(i.e. for building web services).

Register a custom model binder in MVC 4

Solution

Problem