public UtilisationEntity() { InitializeComponent(); var task = ParticipantHelper.SelectLoLPlayersAsync(); task.Wait(); List <Participant_NomCompte> data = task.Result; var tupleList = new List <Tuple <string, string> >(); foreach (var p in data) { tupleList.Add(Tuple.Create(p.Participant.matricule, p.NomCompte)); } dgComptes.ItemsSource = tupleList; }