private void RecupererPeriodeDePlage(string DebutPeriode, string FinPeriode)
 {
     Galatee.Silverlight.ServiceRecouvrement.RecouvrementServiceClient service = new Galatee.Silverlight.ServiceRecouvrement.RecouvrementServiceClient(Utility.ProtocoleFacturation(), Utility.EndPoint("Recouvrement"));
     service.RecupererPeriodeDePlageCompleted += (s, args) =>
     {
         if (args != null && args.Cancelled)
         {
             return;
         }
         if (args.Result == null)
         {
             return;
         }
         var DataSource = args.Result;
         DataSource.ForEach(a => ClasseMEthodeGenerique.FormatPeriodeMMAAAA(a));
         foreach (var item in lbx_Periode.Items)
         {
             DataSource.Add(item.ToString());
         }
         lbx_Periode.Items.Clear();
         foreach (var p in DataSource.OrderBy(p => p))
         {
             var periode = ClasseMEthodeGenerique.FormatPeriodeMMAAAA(p);
             lbx_Periode.Items.Add(periode);
         }
         return;
     };
     service.RecupererPeriodeDePlageAsync(DebutPeriode, FinPeriode);
 }