Using Unity Dependency Injection in WebFormsMVP

As I was preparing a POC for my new project, I stumble upon an idea of using dependency injection / IOC. This is to facilitate the property injection to my Repository or Service classes. Here is the snapshot of the code

Global.asax

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.SessionState;
using Microsoft.Practices.ServiceLocation;
using Microsoft.Practices.Unity;
using Monday.Data;
using Monday.Data.Repositories;
using WebFormsMvp.Binder;
using WebFormsMvp.Unity;

namespace Monday
{
    public class Global : System.Web.HttpApplication
    {
        private readonly IUnityContainer _container;

        public Global()
            : base()
        {
            _container = new UnityContainer();
        }

        void Application_Start(object sender, EventArgs e)
        {
            _container.RegisterInstance<MondayEntities>(
                new MondayEntities(),
                new ContainerControlledLifetimeManager());

            _container.RegisterType<ICountryRepository, CountryRepository>(
                new ContainerControlledLifetimeManager());

            UnityServiceLocator locator = new UnityServiceLocator(_container);
            ServiceLocator.SetLocatorProvider(() => locator);

            PresenterBinder.Factory = new UnityPresenterFactory(_container);

        }

The implementation of the Unity is pretty normal except that I use the ServiceLocator to encapsulate calls to the UnityContainer. Developers may get instance using the following code.

ICountryRepository repo =
    ServiceLocator.Current.GetInstance<ICountryRepository>();

As for codes that want to utilize Property Injection they can implement it in the following way

public class CountryScriptPresenter : Presenter<ICountryScriptView>
{
    private ICountryScriptView _view;

    public CountryScriptPresenter(ICountryScriptView view)
        : base(view)
    {
        _view = view;
        _view.Load += new EventHandler(OnLoad);
    }

    [Dependency]
    public ICountryRepository CountrySource { get; set; }

    private void OnLoad(object sender, EventArgs e)
    {

        if (CountrySource == null)
            throw new ApplicationException("CountryRepository is null or not defined.");

        StringBuilder sb = new StringBuilder();
        StringWriter sw = new StringWriter(sb);

        JsonSerializer serializer = new JsonSerializer();
        serializer.Serialize(sw, CountrySource.GetList());

        _view.Model.List = sb.ToString(); ;
    }
}

The Dependency attribute will handle the injection of the object

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