public void RetourneListeDeSite()
 {
     try
     {
         InterfaceComptableServiceClient service = new InterfaceComptableServiceClient(Utility.ProtocoleFacturation(), Utility.EndPoint("Index"));
         service.RetourneListeDeSiteCompleted += (s, args) =>
         {
             try
             {
                 if (args.Cancelled || args.Error != null || args.Result == null)
                 {
                     string error = args.Error.InnerException.ToString();
                     return;
                 }
                 else
                 {
                     this.CmbSiteEcriture.ItemsSource = null;
                     if (args.Result != null && args.Result.Count != 0)
                     {
                         this.CmbSiteEcriture.ItemsSource       = args.Result;
                         this.CmbSiteEcriture.DisplayMemberPath = "LIBELLE";
                         CmbSiteEcriture.IsEnabled = true;
                     }
                 }
             }
             catch (Exception ex)
             {
                 Message.ShowError(ex, Galatee.Silverlight.Resources.Caisse.Langue.errorTitle);
             }
         };
         service.RetourneListeDeSiteAsync();
     }
     catch (Exception ex)
     {
         throw ex;
     }
 }