使用StructureMap的Asp.Net MVC 5自定义操作过滤器

我的LogAttribute类代码是

public class LogAttribute : ActionFilterAttribute
{
    public ApplicationDbContext Context { get; set; }
    public string Description { get; set; }
    public LogAttribute(string description)
    {
        Description = description;
    }

    public override void OnActionExecuted(ActionExecutedContext filterContext)
    {
        var userId = filterContext.HttpContext.User.Identity.GetUserId();
        var user = Context.Users.Find(userId); **i am getting error here the Context is coming null here** 
        Context.Logs.Add(new Log(user,filterContext.ActionDescriptor.ActionName,filterContext.ActionDescriptor.ControllerDescriptor.ControllerName,Description
                                )
                        );
        Context.SaveChanges();
    }
}

我创建了另一个类,我将值传递给setter依赖项属性

public class StructureMapFilterProvider : FilterAttributeFilterProvider 
{
    private readonly Func<IContainer> _container;
    public StructureMapFilterProvider(Func<IContainer> container)
    {
        _container = container;
    }

    public override IEnumerable<Filter> GetFilters(ControllerContext controllerContext,ActionDescriptor actionDescriptor)
    {
        var filters = base.GetFilters(controllerContext,actionDescriptor);
        var container = _container();
        foreach (var filter in filters)
        {
            container.BuildUp(filter.Instance);
            yield return filter;
        }
    }
}

我的依赖解析器类代码是

public class StructureMapDependencyResolver : IDependencyResolver
{
    private readonly Func<IContainer> _containerFactory;
    public StructureMapDependencyResolver(Func<IContainer> containerFactory)
    {
        _containerFactory = containerFactory;
    }
    public object GetService(Type serviceType)
    {
        if (serviceType == null)
        {
            return null;
        }
        var container = _containerFactory();

        return serviceType.IsAbstract || serviceType.IsInterface
            ? container.TryGetInstance(serviceType)
            : container.GetInstance(serviceType);
    }

    public IEnumerable<object> GetServices(Type serviceType)
    {
        return _containerFactory().GetAllInstances(serviceType).Cast<object>();
    }
}

我的global.ascx代码是

public class MvcApplication : System.Web.HttpApplication
{

    public IContainer Container
    {
        get
        {
            return (IContainer)HttpContext.Current.Items["_Container"];
        }
        set
        {
            HttpContext.Current.Items["_Container"] = value;
        }
    }

    protected void Application_Start()
    {
        AreaRegistration.RegisterAllAreas();
        FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
        RouteConfig.RegisterRoutes(RouteTable.Routes);
        BundleConfig.RegisterBundles(BundleTable.Bundles);
        DependencyResolver.SetResolver(new StructureMapDependencyResolver(() => Container ?? ObjectFactory.Container));

        ObjectFactory.Configure(cfg =>
           {
               cfg.Scan(Scan =>
               {
                   Scan.TheCallingAssembly();
                   Scan.WithDefaultConventions();
                   Scan.With(new ControllerConfiguration());
               });
               cfg.For<IFilterProvider>().Use(new StructureMapFilterProvider(() => Container ?? ObjectFactory.Container));
               cfg.For<IUserStore<ApplicationUser>>()
                  .Use<UserStore<ApplicationUser>>();
               cfg.For<DbContext>()
                  .Use(() => new ApplicationDbContext());
               cfg.SetAllProperties(x =>
                x.Matching(p =>
                     p.DeclaringType.CanBeCastTo(typeof(ActionFilterAttribute)) &&
                     p.DeclaringType.Namespace.StartsWith("TestingSturctureMap") &&
                     p.PropertyType.IsPrimitive &&
                     p.PropertyType != typeof(string)));

           });
    }

    public void Application_BeginRequest()
    {
        Container = ObjectFactory.Container.GetNestedContainer();
    }

    public void Application_EndRequest()
    {
        Container.Dispose();
        Container = null;
    }
}