Action Filter是否可以访问Controller中的私有对象？

public class MyController : Controller
{
    private string _myPrivateObject = "This is a private object";

    [MyActionFilter]
    public IActionResult Index()
    {
        return View();
    }
}

public class MyActionFilterAttribute : ActionFilterAttribute
{
    public override void OnActionExecuting(ActionExecutingContext context)
    {
        MyController controller = context.Controller as MyController;
        string privateObject = controller._myPrivateObject;

        // 在这里可以访问Controller中的私有对象
    }
}