ASP.NET MVC3 + ActionFilterAttribute + Injection？

Question

嘿，我已经succesfull能够在我的FilterAttribute中使用属性注入，但我想知道是否有可能将其移入构造函数呢？

我当前的代码：

// 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 
} 

在此先感谢！

Answer 1

不，这不可能作为构造函数must be simple types的参数。

出于测试目的，你可以有另一个构造函数（因为你不应该使用与测试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

构造方法注入在这种情况下可能的，但你需要使用属性/过滤器组合。

你的过滤器（例如：个IAuthorizationFilter）实现将使用构造函数注入和做所有的工作...

你的属性（例如：FilterAttribute）会瘦，主要是用来装饰你的控制器或动作。

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Ninject容器绑定属性的过滤器：

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

参见：

Dependency Injection with Ninject and Filter attribute for asp.net mvc

Ninject Binding Attribute to Filter with Constructor Arguments

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

我期望克服的诀窍是如何让我的角色在过滤器的属性上定义... ninject文档应该有所帮助，但我并不是自己。

祝你好运。