Entity Framework 第一篇

这段时间研究了orm框架EF 写一写研究的历程和心得

先贴上核心代码

 public interface ITransaction
    {
        bool IsTransaction { get;}  

        void BeginTransaction();

        int Commit();

        void Rollback();
    }

 public class BaseRepository : ITransaction, IDisposable
    {

        private XFDbContext dbContext;

        /// <summary>
        /// 连接字符串名称
        /// </summary>
        public string ConnectionName { get; set; }

        private bool disposed;

        public BaseRepository()
        {
            this.dbContext = new XFDbContext();
            this.IsTransaction = false;
        }

        public BaseRepository(string connectionName)
        {
            this.ConnectionName = connectionName;
            this.dbContext = new XFDbContext(ConnectionName);
            this.IsTransaction = false;
        }

        #region 增删改

        /// <summary>
        /// 新增实体对象
        /// </summary>
        /// <typeparam name="TEntity"></typeparam>
        /// <param name="model"></param>
        /// <returns></returns>
        public int Insert<TEntity>(TEntity model) where TEntity : class
        {
            return this.ChangeObjectState<TEntity>(model, EntityState.Added);
        }

        /// <summary>
        /// 新增实体对象集合
        /// </summary>
        /// <typeparam name="TEntity"></typeparam>
        /// <param name="models"></param>
        /// <returns></returns>
        public int Insert<TEntity>(IEnumerable<TEntity> models) where TEntity : class
        {
            return this.ChangeObjectState<TEntity>(models, EntityState.Added);
        }

        /// <summary>
        /// 持久化对象更改
        /// </summary>
        /// <typeparam name="TEntity"></typeparam>
        /// <param name="model"></param>
        /// <returns></returns>
        public int Update<TEntity>(TEntity model) where TEntity : class
        {
            return this.ChangeObjectState<TEntity>(model, EntityState.Modified);
        }

        /// <summary>
        /// 更新对象集合
        /// </summary>
        /// <typeparam name="TEntity"></typeparam>
        /// <param name="models"></param>
        /// <returns></returns>
        public int Update<TEntity>(IEnumerable<TEntity> models) where TEntity : class
        {
            return this.ChangeObjectState<TEntity>(models, EntityState.Modified);
        }

        /// <summary>
        /// 更新对象部分属性
        /// </summary>
        /// <typeparam name="TEntity"></typeparam>
        /// <param name="predicate"></param>
        /// <param name="updateAction"></param>
        /// <returns></returns>
        public int Update<TEntity>(Expression<Func<TEntity, bool>> predicate, Action<TEntity> updateAction) where TEntity : class
        {
            if (predicate == null)
                throw new ArgumentNullException("predicate");
            if (updateAction == null)
                throw new ArgumentNullException("updateAction");

            //dbContext.Configuration.AutoDetectChangesEnabled = true;
            var _model = dbContext.Set<TEntity>().Where(predicate).ToList();
            if (_model == null) return 0;
            _model.ForEach(p =>
            {
                updateAction(p);
                dbContext.Entry<TEntity>(p).State = EntityState.Modified;
            });
            return Save();
        }

        /// <summary>
        /// 删除实体对象
        /// </summary>
        /// <typeparam name="TEntity"></typeparam>
        /// <param name="model"></param>
        /// <returns></returns>
        public int Delete<TEntity>(TEntity model) where TEntity : class
        {
            return this.ChangeObjectState<TEntity>(model, EntityState.Deleted);
        }

        /// <summary>
        /// 删除实体对象集合
        /// </summary>
        /// <typeparam name="TEntity"></typeparam>
        /// <param name="models"></param>
        /// <returns></returns>
        public int Delete<TEntity>(IEnumerable<TEntity> models) where TEntity : class
        {
            return this.ChangeObjectState<TEntity>(models, EntityState.Deleted);
        }

        /// <summary>
        /// 删除实体对象集合（符合部分条件的）
        /// </summary>
        /// <typeparam name="TEntity"></typeparam>
        /// <param name="predicate"></param>
        /// <returns></returns>
        public int Delete<TEntity>(Expression<Func<TEntity, bool>> predicate) where TEntity : class
        {
            List<TEntity> _list = null;

            _list = dbContext.Set<TEntity>().Where(predicate).ToList();
            foreach (var item in _list)
            {
                dbContext.Entry<TEntity>(item).State = EntityState.Deleted;
            }
            return Save();
        }

        #endregion 增删改

        #region 查询
        public IList<TEntity> Search<TEntity>(Expression<Func<TEntity, bool>> predicate = null) where TEntity : class
        {
            if (predicate == null)
            {
                return dbContext.Set<TEntity>().ToList();
            }
            else
            {
                return dbContext.Set<TEntity>().Where(predicate).ToList();
            }

        }

        /// <summary>
        /// 查询单个记录
        /// </summary>
        /// <typeparam name="TEntity"></typeparam>
        /// <param name="predicate"></param>
        /// <returns></returns>
        public TEntity SearchFirstOrDefault<TEntity>(Expression<Func<TEntity, bool>> predicate = null) where TEntity : class
        {
            if (predicate == null)
            {
                return dbContext.Set<TEntity>().FirstOrDefault();
            }
            else
            {
                return dbContext.Set<TEntity>().Where(predicate).FirstOrDefault();
            }

        }

        /// <summary>
        /// 查询多笔记录
        /// </summary>
        /// <typeparam name="TEntity"></typeparam>
        /// <param name="predicate"></param>
        /// <returns></returns>
        public IList<TEntity> SearchList<TEntity>(Expression<Func<TEntity, bool>> predicate = null) where TEntity : class
        {

            if (predicate == null)
            {
                return dbContext.Set<TEntity>().ToList();
            }
            else
            {
                return dbContext.Set<TEntity>().Where(predicate).ToList();
            }
        }

        public IList<TEntity> GetPaged<TEntity>(out int total, Expression<Func<TEntity, bool>> filter = null, Func<IQueryable<TEntity>, IOrderedQueryable<TEntity>> orderBy = null, int index = 1, int size = 20) where TEntity : class
        {
            int skipCount = (index - 1) * size;
            var query = Get(filter, orderBy);
            total = query.Count();
            query = skipCount > 0 ? query.Skip(skipCount).Take(size) : query.Take(size);
            return query.ToList();
        }

        public IList<TEntity> GetPaged<TEntity>(out int total, Expression<Func<TEntity, bool>> filter = null, string orderBy = null, int index = 1, int size = 20) where TEntity : class
        {
            int skipCount = (index - 1) * size;
            var query = Get(filter, orderBy);
            total = query.Count();
            query = skipCount > 0 ? query.Skip(skipCount).Take(size) : query.Take(size);
            return query.ToList();
        }

        public IQueryable<TEntity> Get<TEntity>(Expression<Func<TEntity, bool>> filter = null, string orderBy = null) where TEntity : class
        {
            IQueryable<TEntity> query = dbContext.Set<TEntity>();
            if (filter != null)
            {
                query = query.Where(filter);
            }
            if (!string.IsNullOrEmpty(orderBy))
            {
                query = query.OrderBy(orderBy);
            }
            return query.AsQueryable();
        }

        public IQueryable<TEntity> Get<TEntity>(Expression<Func<TEntity, bool>> filter = null, Func<IQueryable<TEntity>, IOrderedQueryable<TEntity>> orderBy = null) where TEntity : class
        {
            IQueryable<TEntity> query = dbContext.Set<TEntity>();
            if (filter != null)
            {
                query = query.Where(filter);
            }
            if (orderBy != null)
            {
                orderBy(query).AsQueryable();
            }
            return query.AsQueryable();
        }


        #endregion

        #region 私有方法


        private int Save()
        {
            int effect = 0;
            if (!this.IsTransaction)
            {
                effect = dbContext.SaveChanges();
            }
            return effect;
        }


        /// <summary>
        /// 变更上下文管理器（对象）
        /// </summary>
        /// <typeparam name="TEntity"></typeparam>
        /// <param name="model"></param>
        /// <param name="state"></param>
        private int ChangeObjectState<TEntity>(TEntity model, EntityState state) where TEntity : class
        {
            //_context.Configuration.ValidateOnSaveEnabled = false; 
            dbContext.Entry<TEntity>(model).State = state;
            return Save();

        }

        /// <summary>
        /// 变更上下文管理器(对象集合)
        /// </summary>
        /// <typeparam name="TEntity"></typeparam>
        /// <param name="model"></param>
        /// <param name="state"></param>
        private int ChangeObjectState<TEntity>(IEnumerable<TEntity> model, EntityState state) where TEntity : class
        {
            if (model == null) return 0;

            //_context.Configuration.AutoDetectChangesEnabled = false;
            model.ToList().ForEach(p => dbContext.Entry<TEntity>(p).State = state);
            return Save();

        }


        #endregion

        /// <summary>
        /// 执行带参数的sql语句，返回List
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="strsql"></param>
        /// <param name="paras"></param>
        /// <returns></returns>
        public IEnumerable<T> GetList<T>(string strsql, SqlParameter[] paras)
        {
            return dbContext.Database.SqlQuery<T>(strsql, paras).ToList();
        }

        /// <summary>
        /// 执行不带参数的sql语句，返回list
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="strsql"></param>
        /// <returns></returns>
        public IEnumerable<T> GetList<T>(string strsql)
        {
            return dbContext.Database.SqlQuery<T>(strsql).ToList();
        }

        /// <summary>
        ///  执行带参数的sql语句，返回一个对象
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="strsql"></param>
        /// <param name="paras"></param>
        /// <returns></returns>
        public T GetOneEntity<T>(string strsql, SqlParameter[] paras)
        {
            return dbContext.Database.SqlQuery<T>(strsql, paras).Cast<T>().First();
        }

        /// <summary>
        ///  执行不带参数的sql语句，返回一个对象
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="strsql"></param>
        /// <returns></returns>
        public T GetOneEntity<T>(string strsql)
        {
            return dbContext.Database.SqlQuery<T>(strsql).Cast<T>().First();
        }

        public int ExecuteSqlCommand(string sql, params SqlParameter[] paras)
        {
            if (this.IsTransaction)
            {
                if (dbContext.Database.CurrentTransaction == null)
                {
                    dbContext.Database.BeginTransaction();
                }
            }
            return dbContext.Database.ExecuteSqlCommand(sql, paras);
        }


        /// <summary>
        /// 获取查询数量
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="paras"></param>
        /// <returns></returns>
        public int GetCount(string sql, SqlParameter[] paras)
        {
            return dbContext.Database.SqlQuery(typeof(int), sql, paras).Cast<int>().First();
        }

        public void BeginTransaction()
        {
            this.IsTransaction = true;

        }

        public int Commit()
        {
            int reault = dbContext.SaveChanges();
            this.IsTransaction = false;
            DbContextTransaction transaction = dbContext.Database.CurrentTransaction;
            if (transaction != null)
            {
                transaction.Commit();
                transaction.Dispose();
                reault += 1;
            }

            return reault;
        }

        public void Rollback()
        {
            this.IsTransaction = false;
            DbContextTransaction transaction = dbContext.Database.CurrentTransaction;
            if (transaction != null)
            {
                transaction.Rollback();
                transaction.Dispose();
            }

        }

        public bool IsTransaction
        {
            get;
            private set;
        }

        public void Dispose()
        {
            this.Dispose(true);
            GC.SuppressFinalize(this);
        }

        public virtual void Dispose(bool disposing)
        {
            if (!this.disposed)
            {
                if (disposing)
                {
                    this.dbContext.Dispose();
                }
            }
            this.disposed = true;
        }
    }