How to get the ActionDescription UniqueId from within OnResultExecuted - asp.net-mvc

Question

In ASP.NET MVC, does anyone know a trick to access the ActionDescriptor.UniqueId from within OnResultExecuted? I need to pass information from OnActionExecuting to OnResultExecuted in a way that will work if multiple actions are executed during the one HttpRequest.
For example:
private Dictionary<string,Foo> _foos
{
get { return HttpContext.Current.Items["foos"] as Dictionary<string,Foo>; }
set { HttpContext.Current.Items["foos"] = value; }
}
public override void OnActionExecuting(ActionExecutingContext context)
{
var foos = _foos;
foos[context.ActionDescriptor.UniqueId] = new Foo();
_foos = foos;
}
public override void OnResultExecuted(ResultExecutedContext context)
{
var actionUniqueId = ????
var foo = _foos[actionUniqueId]
}

Answer 1

You can custom the FilterAttributeFilterProvider and ActionFilterAttribute to implement it.
First you can create a filter that inherit the ActionFilterAttribute and contains ActionDescriptor property:
public class MyActionFilterAttribute : ActionFilterAttribute
{
public ActionDescriptor ActionDescriptor { get; set; }
public override void OnResultExecuted(ResultExecutedContext filterContext)
{
var actionUniqueId = ActionDescriptor.UniqueId;
//code..
}
}
Then you need create a filter provider inherit the FilterAttributeFilterProvider and override the GetFilters method:
public class MyFilterProvider : FilterAttributeFilterProvider
{
public override IEnumerable<Filter> GetFilters(ControllerContext controllerContext, ActionDescriptor actionDescriptor)
{
if (controllerContext.Controller != null)
{
foreach (FilterAttribute attr in GetControllerAttributes(controllerContext, actionDescriptor))
{
var myAttr = attr as MyActionFilterAttribute;
if (myAttr != null)
{
myAttr.ActionDescriptor = actionDescriptor;
}
yield return new Filter(attr, FilterScope.Controller, order: null);
}
foreach (FilterAttribute attr in GetActionAttributes(controllerContext, actionDescriptor))
{
var myAttr = attr as MyActionFilterAttribute;
if (myAttr != null)
{
myAttr.ActionDescriptor = actionDescriptor;
}
yield return new Filter(attr, FilterScope.Action, order: null);
}
}
}
}
You can see at the GetFilters method, We set the ActionDescriptor property if the filter type is MyActionFilterAttribute.
Finally, At Global.asax, you need use MyFilterProvider instance to replace the FilterAttributeFilterProvider instance in Providers collection:
public class MvcApplication : System.Web.HttpApplication
{
protected void Application_Start()
{
//replace the FilterAttributeFilterProvider in providers collection
for (int i = 0; i < FilterProviders.Providers.Count; i++)
{
if (FilterProviders.Providers[i] is FilterAttributeFilterProvider)
{
FilterProviders.Providers[i] = new MyFilterProvider();
break;
}
}
//other global init code...
}
}