MongoDB C#samus驱动

public class MongoDB<T>where T: class,new()
    {
        private string connectionString = ConfigurationManager.AppSettings["mongodbConnection"];
        private string dataBase= ConfigurationManager.AppSettings["mongodbBase"];
        private string collection= ConfigurationManager.AppSettings["mongodbCol"];
        private Mongo mongo = null;
        public MongoDB(string connectionStr,string dbBase,string col)
        {
            if (connectionStr != "") { connectionString = connectionStr; }
            if (dbBase != "") dataBase = dbBase;
            if (col != "") collection = col;
        }
        /// <summary>
        /// 实现linq查询的映射配置
        /// </summary>
        public MongoConfiguration configuration
        {
            get {
                var config = new MongoConfigurationBuilder();
                config.Mapping(mapping => { 
                     mapping.DefaultProfile(profile => {
                         profile.SubClassesAre(t => t.IsSubclassOf(typeof(T)));
                         mapping.Map<T>();
                        
                     });
                });
                config.ConnectionString(connectionString);
                return config.BuildConfiguration();
            }
        }
       //得到collecaton
        public IMongoCollection<T> GetMongoDBCollction()
        {
            mongo = new Mongo(configuration);
            try
            {
                mongo.Connect();
                var db = mongo.GetDatabase(dataBase);
                return db.GetCollection<T>(collection);
            }
            catch (Exception ex) { throw; }
           
        }

      
        /// <summary>
        /// 添加
        /// </summary>
        /// <param name="t"></param>
        public void Insert(T t)
        {
            
                try
                {
                    var col= GetMongoDBCollction();
                    col.Insert(t, true);
                }
                catch (Exception ex) { throw; } 
                finally {
                    mongo.Disconnect();
                }
            
        }
        /// <summary>
        /// 更新
        /// </summary>
        /// <param name="t"></param>
        /// <param name="func">where的lambda条件</param>
        public void Update(T t, Expression<Func<T, bool>> func)
        {
           
                try
                {
                    var col = GetMongoDBCollction();
                    col.Update<T>(t, func, true);
                }
                catch (Exception ex) { throw; }
                finally { mongo.Disconnect(); }
           
               
        }
        /// <summary>
        /// 分页
        /// </summary>
        /// <param name="pageSize">每页多少条</param>
        /// <param name="pageIndex">当前页</param>
        /// <param name="func">where的lambda条件</param>
        /// <param name="pageCount">总共多少条</param>
        /// <returns></returns>
        public List<T> GetPages<TKey>(int pageSize, int pageIndex, Expression<Func<T, bool>> func, Expression<Func<T, TKey>> orderBy, out int pageCount)
        {
            pageCount = 0;

            try
            {
                var col = GetMongoDBCollction();

                List<T> list = null;
                if (func != null)
                {
                    pageCount = col.Linq().Where(func).ToList().Count;
                    if (orderBy != null)
                    {
                        list = col.Linq().Where(func).OrderByDescending(orderBy).Skip((pageIndex - 1) * pageSize).Take(pageSize).ToList();
                    }
                    else
                    {
                        list = col.Linq().Where(func).Skip((pageIndex - 1) * pageSize).Take(pageSize).ToList();
                    }
                }
                else
                {
                    pageCount = col.Linq().ToList().Count;
                    if (orderBy != null)
                    {
                        list = col.Linq().OrderByDescending(orderBy).Skip((pageIndex - 1) * pageSize).Take(pageSize).ToList();
                    }
                    else
                    {
                        list = col.Linq().Skip((pageIndex - 1) * pageSize).Take(pageSize).ToList();
                    }
                }
                return list;
            }
            catch (Exception ex) { throw; }
            finally { mongo.Disconnect(); }

        }
       //linq 分页
        public List<T> GetLinqPages<TKey>(int pageSize, int pageIndex, Expression<Func<T, bool>> func, Expression<Func<T, TKey>> orderBy, out int pageCount) 
        {
             pageCount = 0;
            try
            {
                var col = GetMongoDBCollction();
                List<T> list = null;
                var query = from a in col.Linq()  select a;
                if (func!=null)
                {
                    query=query.Where(func);
                }
                if (orderBy != null)
                {
                    query = query.OrderByDescending(orderBy);
                }
                pageCount = query.ToList().Count;
                list = query.Skip((pageIndex - 1) * pageSize).Take(pageSize).ToList();
                return list;
            }
            catch { throw; }
            finally { mongo.Disconnect(); }
        }

        /// <summary>
        /// 读取一条数据
        /// </summary>
        /// <param name="func"></param>
        /// <returns></returns>
        public T GetSingle(Expression<Func<T, bool>> func)
        {
            using (Mongo mongo = new Mongo(configuration))
            {
                try {
                    var col = GetMongoDBCollction();
                    return col.FindOne(func);
                } catch (Exception e) { throw; } finally { mongo.Disconnect(); }
            }
        }

        public void Delete(Expression<Func<T, bool>> func)
        {
            using (Mongo mongo = new Mongo(configuration))
            {
                try {
                    var col = GetMongoDBCollction();
                    //这个地方要注意，一定要加上T参数，否则会当作object类型处理
                    //导致删除失败
                    col.Remove<T>(func);
                } catch (Exception e) { throw; } finally { mongo.Disconnect(); }
            }
        }
        /// <summary>
        /// 得到总数量
        /// </summary>
        /// <param name="func"></param>
        /// <returns></returns>
        public int GetCount(Expression<Func<T, bool>> func)
        {
            using (Mongo mongo = new Mongo(configuration))
            {
                try {
                    var col = GetMongoDBCollction();
                    return col.Linq().Where(func).ToList().Count;
                } catch (Exception e) { throw; } finally { mongo.Disconnect(); }

            }
        }
    }