Allows you to check what the current action is on action filters, e.g: if (filterContext.ActionDescriptor.DescribesAction<AccountController>(a => a.Login())) { Do(stuff); }

ActionDescriptorDescribesActionExtension.cs

using System;
using System.Linq.Expressions;
using System.Web.Mvc;

public static class ActionDescriptorDescribesActionExtension
{
  public static bool DescribesAction<TController>(this ActionDescriptor self, Expression<Func<TController, object>> action) where TController : IController
	{
		var actionName =
			(action.Body is UnaryExpression
			 	? (MethodCallExpression)((UnaryExpression)action.Body).Operand
			 	: (MethodCallExpression)action.Body).Method.Name;

		var controller = typeof(TController);

		return actionName == self.ActionName && controller == self.ControllerDescriptor.ControllerType;
	}
}