Question

当我尝试在属性上调用DependencyResolver时返回null，我在项目中使用Unity.WebAPI。这是我的代码：

[AttributeUsage(AttributeTargets.Method | AttributeTargets.Class, AllowMultiple = false)]
public class MSIAuthorizeAttribute : AuthorizationFilterAttribute
{
    private bool _perUser;
    private ISecurityService _securityService;

    /// <summary>
    /// constractor for MSIAuthorizeAttribute
    /// </summary>
    public MSIAuthorizeAttribute(bool perUser = true)
    {
        _perUser = perUser;
    }
    public override void OnAuthorization(HttpActionContext actionContext)
    {
        var persistenceService = DependencyResolver.Current.GetService<IPersistenceService>();
        var logService = DependencyResolver.Current.GetService<ILogService>();
        var vbUtilities = DependencyResolver.Current.GetService<IVBUtilities>();
        _securityService = new SecurityService(persistenceService,logService,vbUtilities);
        ...
    }
}

Answer 1

致Janki

我找到了答案，您需要在定义依赖注入容器的位置注册过滤器。这是一个例子：

public static void RegisterFilterProviders(HttpConfiguration config)
{
    var providers = config.Services.GetFilterProviders().ToList();
    config.Services.Add(typeof(IFilterProvider), new UnityActionFilterProvider(GetConfiguredContainer()));

    var defaultprovider = providers.First(p => p is ActionDescriptorFilterProvider);
    config.Services.Remove(typeof(IFilterProvider), defaultprovider);
}

然后在WebApiConfig.cs中添加以下代码行：

UnityConfig.RegisterFilterProviders(config);

Answer 2

我找到了解决方案：

[AttributeUsage(AttributeTargets.Method | AttributeTargets.Class, AllowMultiple = false)]
public class MSIAuthorizeAttribute : System.Web.Http.Filters.ActionFilterAttribute
{
    private bool _perUser;
    private ISecurityService _securityService;
    [Dependency]
    public ILogService LogService { get; set; }
    [Dependency]
    public IVBUtilities VbUtilities { get; set; }
    [Dependency]
    public IPersistenceService PersistenceService { get; set; }

    /// <summary>
    /// constractor for MSIAuthorizeAttribute
    /// </summary>
    public MSIAuthorizeAttribute( bool perUser = true)
    {
        _perUser = perUser;
    }

    public override void OnActionExecuted(HttpActionExecutedContext actionContext)
    {...}

http://unity.codeplex.com/discussions/446780

无法获得统一DependencyResolver在web api过滤器中工作

2 个答案: