void CommandAddActorExecute()
        {
            bool exist = false;

            foreach (MovieNET.Actor actor in ListActor)
            {
                if (actor.Firstname == ActorFirstname && actor.Lastname == actorLastname)
                {
                    exist = true;
                }
            }
            if (exist == false)
            {
                serviceClient.CreateActor(ActorFirstname, ActorLastname);
            }
            ListActor      = serviceClient.SelectAllActor();
            ActorFirstname = "";
            ActorLastname  = "";
        }