如何在多个控制器的多个动作中实现一些代码

Question

我有带动作的控制器，它与某些实体（驱动程序）一起工作。此外，每个驱动程序都与身份配置文件相关联。

        public async Task<ActionResult> Details(int? id)
        {
            if ((id == null))
            {
                return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
            }
            DriverDetailVM model = mapper.Map<DriverDetailVM>(db.Drivers.Find(id));
            if ((model == null))
            {
                return HttpNotFound();
            }
            return View(model);
        }

        public async Task<ActionResult> Edit(int? id = null, bool isNewUser = false)
        {
/////////
        }

如果用户具有 "Superadmin" 角色，那么他可以访问具有任何 id 值的页面。如果用户具有 "Driver" 角色，那么只有当 id 值与他的个人资料相同时，我们才能访问。我尝试在 ActionFilter 上实现它：

public class DriverAccessActionFilterAttribute : ActionFilterAttribute
{
    public string IdParamName { get; set; }
    public int DriverID { get; set; }

    public override void OnActionExecuting(ActionExecutingContext filterContext)
    {
        if (filterContext.HttpContext.User.IsInRole("Driver"))
        {
            if (filterContext.ActionParameters.ContainsKey(IdParamName))
            {
                var id = filterContext.ActionParameters[IdParamName] as Int32;
                if (id != DriverID)
                    filterContext.Result = new HttpStatusCodeResult(HttpStatusCode.Forbidden);
            }
            else
                filterContext.Result = new HttpStatusCodeResult(HttpStatusCode.BadRequest); 
        }
        else
            base.OnActionExecuting(filterContext);
    }
}

但是当我尝试使用此代码时：

    [DriverAccessActionFilter(DriverID = currentUser.DriverId, IdParamName = "id")]
    public async Task<ActionResult> Details(int? id)
    {

不想编译，因为

An object reference is required for the non-static field, method, or property

如何实现？

Answer 1

属性参数在编译时计算，而不是在运行时计算。所以它们必须是编译时常量。您不能在运行时将值传递给操作属性。也就是说，在 [DriverAccessActionFilter(DriverID = currentUser.DriverId, IdParamName = "id")] 中，您超过了 DriverID = currentUser.DriverId。属性用作 controller/action 元数据，需要在程序集中编译元数据。这就是属性只能取常量值的原因。

您必须按如下方式更改您的属性：

使用依赖注入注入您的服务，returns 登录用户。
或者实施自定义委托人并为其分配当前请求委托人。

如果您实施 CustomPrinicpal，您可以按如下方式修改您的属性：

public class DriverAccessActionFilterAttribute : ActionFilterAttribute
    {
        public string IdParamName { get; set; }
        private int DriverID { get; set; }

        public override void OnActionExecuting(ActionExecutingContext filterContext)
        {            
            if (filterContext.HttpContext.User.IsInRole("Driver"))
            {
                var customPrincipal = filterContext.HttpContext.User as CustomPrincipal;
                DriverID = customPrincipal.Id;
                // Rest of you logic                
            }
            else
                base.OnActionExecuting(filterContext);
        }
    }

如果您选择 DI 路径，则可以使用以下代码段：

public class DriverAccessActionFilterAttribute : ActionFilterAttribute
{
    public string IdParamName { get; set; }
    private int DriverID { get; set; }

    public DriverAccessActionFilterAttribute(IYourIdentityProvider provider)
    {
        DriverID = provider.LoggedInUserID;
    }

    public override void OnActionExecuting(ActionExecutingContext filterContext)
    {            
        // Your logic
    }
}

然后将您的属性用作 [DriverAccessActionFilter(IdParamName = "id")]

如何在多个控制器的多个动作中实现一些代码

How to implement some code in many actions of many controllers

asp.net-mvc

custom-action-filter

action-filter

actionfilterattribute