偶得--Unity在asp.net mvc上的基本应用

最近在研究Oxite，发现在这个程序中，大量采用了Unity这个微软的IOC框架。过去我对于IOC的了解，还只停留在“城堡”阶段。所以最近对Unity这个框架进行了下小小的补课，现在就将一个简单的应用拿出来跟大家分享。

首先，我有个主页HOME

 

public class HomeController : Controller

在它下面有个Index，在这个页面上有个主页信息，需要从数据库上获取，我们首先先创建一个获取这个信息的接口

    public interface IGetHomeInfo
    {
        string GetHomeTitle();
    }

然后，实现它的一种方式

 

    public class GetHome : IGetHomeInfo
    {

        #region IGetHomeInfo 成员

        public string GetHomeTitle()
        {
            DataService ds = new DataService();
            return ds.GetHomeTitle();
        }

        #endregion
    }

然后，我们先在index页面的Controller中，加入这个接口

 

    public class HomeController : Controller
    {

        [Dependency]
        public IGetHomeInfo getHomeTitle { get; set; }

 

        [LoggerFilter()]
        [ExceptionFilter()]
        public ActionResult Index(int? id)
        {
            DataService ds = new DataService();
            ViewData["HomeTitle"] = getHomeTitle.GetHomeTitle();
            ViewData["Id"] = id.ToString();
            return View();
        }

好了，现在我们在Index(int? id)中放入了一个IGetHomeInfo 类型的注入接口，下面我们就把GetHome 注入到这个位置

    public interface IContainerAccessor
    {
        IUnityContainer Container { get; }
    }

 

 

public class MvcApplication : System.Web.HttpApplication, IContainerAccessor

    {
        private static UnityContainer _container;

        public static IUnityContainer Container
        {
            get { return _container; }
        }

 

        IUnityContainer IContainerAccessor.Container
        {
            get { return Container; }
        }

        public static void RegisterRoutes(RouteCollection routes)
        {
            routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

            routes.MapRoute(
                "Default",                                              // Route name
                "{controller}/{action}/{id}",                           // URL with parameters
                new { controller = "Test", action = "Index", id = "" }  // Parameter defaults
            );

        

        }

        protected void Application_Start()
        {
            AreaRegistration.RegisterAllAreas();

            RegisterRoutes(RouteTable.Routes);

            if (_container == null)
                _container = new UnityContainer();

            IControllerFactory controllerFactory =
                new UnityControllerFactory(_container);

            ControllerBuilder.Current.SetControllerFactory(controllerFactory);

            _container.RegisterType<IGetHomeInfo, GetHome>    //在这里完成了具体的接口-类型绑定
                (new ContainerControlledLifetimeManager());

　　　　_container.RegisterType<IActionInvoker, BYSJControllerActionInvoker>();
        }
    }

最后，我们还需要完成UnityControllerFactory它继承自DefaultControllerFactory，代码如下：

 

public class UnityControllerFactory : DefaultControllerFactory
    {
        IUnityContainer _container;

        public UnityControllerFactory(IUnityContainer container)
        {
            _container = container;
        }

        protected override IController GetControllerInstance(System.Web.Routing.RequestContext requestContext,Type controllerType)
        {
            if (controllerType == null)
                throw new ArgumentNullException("controllerType");

            if (!typeof(IController).IsAssignableFrom(controllerType))
                throw new ArgumentException(string.Format(
                    "Type requested is not a controller: {0}", controllerType.Name),
                    "controllerType");

            IController ic  = _container.Resolve(controllerType) as IController;
            if (typeof(Controller).IsAssignableFrom(controllerType))
            {
                Controller controller = ic as Controller;

                if (controller != null)
                    controller.ActionInvoker = _container.Resolve<IActionInvoker>();

                return ic;
            }

            return ic;
        }
    }

 

这样，一个简单的IOC注入就完成了，至于程序中的IActionInvoker是怎么回事，我们留到下回再说