public class TrackActionFilterAttribute : ActionFilterAttribute, IActionFilter
{
   public override void OnActionExecuting(ActionExecutingContext filterContext)
   {
      Tracking track = new Tracking()
      {
        Action = filterContext.ActionDescriptor.ControllerDescriptor.ControllerName + filterContext.ActionDescriptor.ActionName
      };
      context.Trackings.Add(track);
      context.SaveChanges();
   }
}

[TrackActionFilter]
public ActionResult Index()
{
  if (Request.Form["registered"] == 1)
     return PartialView("Landing");
  else
     return PartialView("Register");
}

[TrackActionFilter]
public ActionResult Landing()
{
   return PartialView();
}

[TrackActionFilter]
public ActionResult Register()
{
   return PartialView();
}

filterContext.HttpContext.Request["registered"]

public override void OnActionExecuted(ActionExecutedContext filterContext)
{
    var viewResult = filterContext.Result as ViewResultBase;
    if (viewResult != null)
    {
        // the controller action returned either a View or a partialView
        // => we could get its name:
        var name = viewResult.ViewName;
    }

    ...
}