public void Add(TrainRoute trainRoute)
        {
            var db = MongoDbManager <TrainRoute> .MongoDb(CollectionName);

            if (db != null)
            {
                db.Save(trainRoute);
            }
        }
        public TrainRoute Find(string fromId, string toId)
        {
            var db = MongoDbManager <TrainRoute> .MongoDb(CollectionName);

            if (db == null)
            {
                return(null);
            }
            return(db.Find(string.Concat(fromId, "-", toId)));
        }