/// <summary>
        /// 數據庫連接
         /// </summary>
        private const string conn = "mongodb://127.0.0.1:27017";
        /// <summary>
        /// 指定的數據庫
         /// </summary>
        private const string dbName = "mongodb_name";
        /// <summary>
        /// 指定的表
         /// </summary>
        private const string tbName = "table_text";
　　　　　//創建數據連接
         MongoServer server = MongoServer.Create(conn);
            //獲取指定數據庫
         MongoDatabase db = server.GetDatabase(dbName);
            //獲取表
         MongoCollection col = db.GetCollection(tbName);

        /// <summary>
        /// 添加
        /// </summary>
        /// <param name="text">內容</param>
        /// <param name="articleId">文章ID</param>
        /// <param name="channelId">頻道ID</param>
        /// <returns></returns>
        public static void Add(User t)
        {
            //創建數據連接
            MongoServer server = MongoServer.Create(conn);
            //獲取指定數據庫
            MongoDatabase db = server.GetDatabase(dbName);
            //獲取表
            MongoCollection col = db.GetCollection(tbName);
            //插入
            col.Insert(t);

        }

        /// <summary>
        /// 根據ObjectID 刪除
        /// </summary>
        /// <param name="objId"></param>
        public static void Delete(string objId)
        {
            //創建數據連接
            MongoServer server = MongoServer.Create(conn);
            //獲取指定數據庫
            MongoDatabase db = server.GetDatabase(dbName);
            //獲取表
            MongoCollection<User> col = db.GetCollection<User>(tbName);

            IMongoQuery query = Query.EQ("_id", new ObjectId(objId));

            col.Remove(query);
        }

        /// <summary>
        /// 根據ObjectID 修改
        /// </summary>
        public static void Update(User t)
        {
            //創建數據連接
            MongoServer server = MongoServer.Create(conn);
            //獲取指定數據庫
            MongoDatabase db = server.GetDatabase(dbName);
            //獲取表
            MongoCollection<User> col = db.GetCollection<User>(tbName);

            BsonDocument bd = BsonExtensionMethods.ToBsonDocument(t);

            IMongoQuery query = Query.EQ("_id", t.Id);

            col.Update(query, new UpdateDocument(bd));

        }

        /// <summary>
        /// 根據ObjectID 查詢
        /// </summary>
        public static TuCao SelectOne(string objId)
        {
            //創建數據連接
            MongoServer server = MongoServer.Create(conn);
            //獲取指定數據庫
            MongoDatabase db = server.GetDatabase(dbName);
            //獲取表
            MongoCollection<User> col = db.GetCollection<User>(tbName);
            //條件查詢           
            return col.FindOne(Query.EQ("_id", new ObjectId(objId)));
        }

        /// <summary>
        /// 查詢所有
        /// </summary>
        public static void SelectAll()
        {
            List<User> list = new List<User>();

            //創建數據連接
            MongoServer server = MongoServer.Create(conn);
            //獲取指定數據庫
            MongoDatabase db = server.GetDatabase(dbName);
            //獲取表
            MongoCollection<User> col = db.GetCollection<User>(tbName);
            //查詢全部
            list.AddRange(col.FindAll());

            //--------------------------------
            foreach (TuCao t in col.FindAll())
            {
                string id = t.Id.ToString();
                string text = t.Text;
                DateTime dt = t.Createdate;
            }
        }