Action filter execution order

vtortola picture vtortola · Oct 25, 2011 · Viewed 20.8k times · Source

I have created two classes that implement AuthorizeAttribute.

One is used globally, and I set it on the Global.asax.cs:

filters.Add(new FirstAuthorizeAttribute() { Order = 0 });

The other is called SecondAuthorizeAttribute and it is used only in some action methods, and I use it as attribute in the methods I want.

    [HttpGet]
    [SecondAuthorize]
    public ActionResult LogOut()
    {
        FormsAuthentication.SignOut();
        Session.Clear();
        Session.Abandon();
        return Redirect(Url.Content("~/"));
    }

The problem is that SecondAuthorizeAttribute always execute before FirstAuthorizeAttribute, and I need this one to execute first. The order is not being helpful, how could I do it?

Answer

freedomn-m picture freedomn-m · Jun 8, 2015

The link in @HectorCorrea's answer is dead at the moment, here's the content retrieved and summarised from the current Google cache (in case that also goes) :

Filters execute in this order:

  • Authorization filters
  • Action filters
  • Response/Result filters
  • Exception filters

Within each filter, you may specify the Order property. (All filters are derived from the abstract class FilterAttribute, and this class has an Order property). This property will ensure the filter runs in a specific Order.

eg:

[AuthorizationFilterA(Order=2)]
[AuthorizationFilterB(Order=1)]
public ActionResult Index()
{          
    return View();
}

There's also FilterScope and, by default, the filter with the lowest scope runs first when the order is the same (or not specified):

namespace System.Web.Mvc {
    public enum FilterScope {
        First = 0,
        Global = 10,
        Controller = 20,
        Action = 30,
        Last = 100,
    }
}

If no order is specified, the order value is -1 (first, not last).

Controllers themselves can be filters and will run with order Int32.MinValue