ASP.NET MVC3 + ActionFilterAttribute +注入？

Question

嘿那里，我已經成功地在我的FilterAttribute中使用了屬性注入，但是我想知道它是否可以將它移動到構造函數中呢？

我目前的代碼：

// AuthAttribute.cs

public class AuthAttribute : ActionFilterAttribute
{
    public Roles _authRoles { get; private set; }

    [Inject]
    private readonly IAuthorizationService _service;

    public AuthAttribute(Roles roles)
    {
        _authRoles = roles;
    }

    public override void OnActionExecuting(ActionExecutingContext filterContext)
    {
        if (!filterContext.HttpContext.User.Identity.IsAuthenticated)
        {
            string redirectOnSuccess = filterContext.HttpContext.Request.Url.AbsolutePath;
            string redirectUrl = string.Format("?returnUrl={0}", redirectOnSuccess);
            string loginUrl = FormsAuthentication.LoginUrl + redirectUrl;

            filterContext.HttpContext.Response.Redirect(loginUrl, true);
        }
        else
        {
            bool isAuthorized = _service.Authorize(GetUserSession.Id, _authRoles.ToString());

            if (!isAuthorized)
            {
                // TODO: Make custom "Not Authorized" error page.
                throw new UnauthorizedAccessException("No access");
            }
        }
    }
}

// TestController.cs

[Auth(Roles.Developer)]
public ActionResult Index()
{
    // Some smart logic
}

提前致謝！

Answer 1

不，這是不可能的，因為構造函數的參數必須是簡單類型 。

出於測試目的，您可以使用另一個構造函數（因為您不應該使用帶有測試的IoC容器）：

public class AuthAttribute : ActionFilterAttribute
{
    public Roles _authRoles { get; private set; }

    [Inject]
    private readonly IAuthorizationService _service;

    public AuthAttribute(Roles roles)
    {
        _authRoles = roles;
    }

    public AuthAttribute(Roles roles, IAuthorizationService authSvc)
        : this(roles)
    {
        this.service = authSvc;
    }

    // ...
}

Answer 2

構造函數注入有可能在這種情況下，但你需要使用屬性/過濾器組合。

您的過濾器（例如：IAuthorizationFilter）實現將使用構造函數注入並完成所有工作...

您的屬性（例如：FilterAttribute）將很薄，主要用於裝飾您的控制器或操作。

public class AuthorizationFilter : IAuthorizationFilter
{
    private readonly IAuthorizationService _authorizationService;
    private readonly UserRoles _requiredRoles; // Enum of Roles

    public AuthorizationFilter(IAuthorizationService authorizationService, UserRoles requiredRoles)
    {
        _authorizationService = authorizationService;
        _requiredRoles = requiredRoles;
    }

    public void OnAuthorization(AuthorizationContext filterContext)
    {
        // do work, or HandleUnauthorizedRequest()
    }

    protected void HandleUnauthorizedRequest(AuthorizationContext filterContext)
    {
        // do work
    }

}

public class RequireRolesAttribute : FilterAttribute
{
    public readonly UserRoles RequiredRoles;

    public RequireRolesAttribute(UserRoles requiredRoles)
    {
        RequiredRoles = requiredRoles;
    }        
}

然后你的Ninject容器將屬性綁定到過濾器：

// controller-level
kernel.BindFilter<AuthorizationFilter>(FilterScope.Controller, 0).WhenControllerHas<RequireRolesAttribute>()
// action level
kernel.BindFilter<AuthorizationFilter>(FilterScope.Action, 0).WhenActionMethodHas<RequireRolesAttribute>();

看到：

asp.net mvc的Ninject和Filter屬性的依賴注入

使用構造函數參數過濾的Ninject綁定屬性

https://github.com/ninject/ninject.web.mvc/wiki/Filter-configurations

我想要克服的技巧是如何將我的角色定義在屬性上的過濾器... ninject文檔應該有所幫助，但我自己還沒有。

祝好運。