asp.net-mvc – 使用ASP.New MVC 4 Web Api进行授权过滤依赖注入

public class UnityWebApiFilterAttributeFilterProvider : ActionDescriptorFilterProvider,System.Web.Http.Filters.IFilterProvider
{
    private readonly IUnityContainer _container;

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

    public IEnumerable<FilterInfo> GetFilters(HttpConfiguration configuration,HttpActionDescriptor actionDescriptor)
    {
        var filters = base.GetFilters(configuration,actionDescriptor);

        this.BuildUpAttributes(filters);

        return filters;
    }

    private void BuildUpAttributes(IEnumerable filterInfo)
    {
        foreach (FilterInfo filter in filterInfo)
        {
            object o = _container.BuildUp(filter.GetType(),filter);
        }
    }
}

我将此提供程序设置为我的Global.asax文件中的默认提供程序：

var providers = GlobalConfiguration.Configuration.Services.GetFilterProviders().ToList();
        //Remove the default provider
        var defaultprovider = providers.Single(i => i is ActionDescriptorFilterProvider);
        GlobalConfiguration.Configuration.Services.Remove(typeof(System.Web.Http.Filters.IFilterProvider),defaultprovider);
        //Add our custom provider
        GlobalConfiguration.Configuration.Services.Add(typeof(System.Web.Http.Filters.IFilterProvider),new UnityWebApiFilterAttributeFilterProvider(new UnityContainer()));

我还在AuthorizationFilter中添加了一个依赖项：

public class WebApplicationApiAuthorizeAttribute : System.Web.Http.AuthorizeAttribute
{

    [Dependency]
    public IAuthorizationHelper AuthorizationHelper { get; set; }

    #region OnAuthorization
    public override void OnAuthorization(System.Web.Http.Controllers.HttpActionContext actionContext)
{
    //Authorization code,which uses the AuthorizationHelper lives here
}   

}

我在Unity配置文件中设置了一个映射：

container.RegisterType<WebApplicationApiAuthorizeAttribute>(new InjectionMember[]
            {
                new InjectionProperty("AuthorizationHelper",new ResolvedParameter<IAuthorizationHelper>())
            });

        container.RegisterType<IAuthorizationHelper,WebAuthorizationHelper>(new InjectionMember[]
            {
                new InjectionProperty("Cache",new ResolvedParameter<ICache>(cacheType)),new InjectionProperty("UserSessionManager",new ResolvedParameter<IUserSessionManager>()),new InjectionProperty("AuthorizationPermissionManager",new ResolvedParameter<IAuthorizationPermissionManager>()),new InjectionProperty("ExceptionLogger",new ResolvedParameter<IExceptionLogger>()),});

我可以看到UnityWebApiFilterAttributeFilterProvider类中的“BuildUpAttributes”方法已执行,并且过滤器已传递到_container.BuildUp(…)方法,但是,WebApplicationApiAuthorizeAttribute中的“IAuthorizationHelper”依赖关系无法解析.当我调试WebApplicationApiAuthorizeAttribute时,它为null.

那么为什么这种依赖性没有被解决？