public void DeleteTodoItem(string id)
 {
     try
     {
         var todoItem = todoService.Find(id);
         if (todoItem != null)
         {
             todoService.DeleteData(id);
         }
         else
         {
             throw new FaultException("TodoItem not found");
         }
     }
     catch (Exception ex)
     {
         throw new FaultException(string.Format("Error: {0}", ex.Message));
     }
 }