Unity MVC 3 Dependency Resolver

AppStart_Unity.cs

using System.Configuration;
using System.Web.Mvc;
using Microsoft.Practices.Unity;

[assembly: WebActivator.PreApplicationStartMethod(typeof(WebApplication.App_Start.AppStart_Unity), "Start")]

namespace WebApplication.App_Start
{
    public class AppStart_Unity
    {
        public static void Start()
        {
            // Create unity container
            var container = new UnityContainer();

            // register services with the container.
            RegisterServices(container);

            // Tell MVC 3 to use Unity DI container.
            DependencyResolver.SetResolver(
                serviceType =>
                {
                    try { return container.Resolve(serviceType); }
                    catch { return null; }
                },
                serviceType =>
                {
                    try { return container.ResolveAll(serviceType); }
                    catch { return null; }
                });

            // Register Unity with Common Serivice Locator also
            Microsoft.Practices.ServiceLocation.ServiceLocator.SetLocatorProvider(
                () => new UnityServiceLocator(container));
        }

        public static void RegisterServices(IUnityContainer container)
        {
            // register types here
        }
    }
}