public class SpecialActionFilter : ActionFilterAttribute
{
    public override void OnActionExecuting(ActionExecutingContext filterContext)
    {
        foreach (string value in filterContext.Controller.ValueProvider.Keys)
        {
            string h = filterContext.Controller.ValueProvider[value].AttemptedValue;

            if (h == "1")
            {
                //set the value of the key to be say "one".
            }
        }

        base.OnActionExecuting(filterContext);
    }

}