public void getFieldById(Action<FieldModel> callback, int id)
 {
     getFieldByIdCallback = callback;
     FieldServiceClient fieldSvc = new FieldServiceClient();
     fieldSvc.SelectFieldByIdCompleted += new EventHandler<SelectFieldByIdCompletedEventArgs>
         (fieldSvc_SelectFieldByIdCompleted);
     fieldSvc.SelectFieldByIdAsync(id);
 }