/// <summary>    /// 数据仓储类    /// </summary>    /// <typeparam name="T">实体模型</typeparam>    public class Repository<T> where T : class    {        /// <summary>        /// 数据上下文        /// </summary>        public DbContext DbContext { get; set; }        public Repository()        { }        /// <summary>        /// 构造函数        /// </summary>        /// <param name="dbContext">数据上下文</param>        public Repository(DbContext dbContext)        {            DbContext = dbContext;        }        //查找实体        #region Find        /// <summary>        /// 查找实体        /// </summary>        /// <param name="ID">实体主键值</param>        /// <returns></returns>        public T Find(int ID)        {            return DbContext.Set<T>().Find(ID);        }        /// <summary>        /// 查找实体        /// </summary>        /// <param name="where">查询Lambda表达式</param>        /// <returns></returns>        public T Find(Expression<Func<T, bool>> where)        {            return DbContext.Set<T>().SingleOrDefault(where);        }        #endregion        //查找实体列表        #region FindList        /// <summary>        /// 查找实体列表        /// </summary>        /// <returns></returns>        public IQueryable<T> FindList()        {            return DbContext.Set<T>();        }        /// <summary>        /// 查找实体列表        /// </summary>        /// <param name="where">查询Lambda表达式</param>        /// <returns></returns>        public IQueryable<T> FindList(Expression<Func<T, bool>> where)        {            return DbContext.Set<T>().Where(where);        }        /// <summary>        /// 查找实体列表        /// </summary>        /// <param name="where">查询Lambda表达式</param>        /// <param name="number">获取的记录数量</param>        /// <returns></returns>        public IQueryable<T> FindList(Expression<Func<T, bool>> where, int number)        {            return DbContext.Set<T>().Where(where).Take(number);        }        /// <summary>        /// 查找实体列表        /// </summary>        /// <param name="where">查询Lambda表达式</param>        /// <param name="orderParam">排序参数</param>        /// <returns></returns>        public IQueryable<T> FindList(Expression<Func<T, bool>> where, OrderParam orderParam)        {            return FindList(where, orderParam, 0);        }        /// <summary>        /// 查找实体列表        /// </summary>        /// <param name="where">查询Lambda表达式</param>        /// <param name="orderParam">排序参数</param>        /// <param name="number">获取的记录数量【0-不启用】</param>        public IQueryable<T> FindList(Expression<Func<T, bool>> where, OrderParam orderParam, int number)        {            OrderParam[] _orderParams = null;            if (orderParam != null) _orderParams = new OrderParam[] { orderParam };            return FindList(where, _orderParams, number);        }        /// <summary>        /// 查找实体列表        /// </summary>        /// <param name="where">查询Lambda表达式</param>        /// <param name="orderParams">排序参数</param>        /// <param name="number">获取的记录数量【0-不启用】</param>        /// <returns></returns>        public IQueryable<T> FindList(Expression<Func<T, bool>> where, OrderParam[] orderParams, int number)        {            var _list = DbContext.Set<T>().Where(where);            var _orderParames = Expression.Parameter(typeof(T), "o");            if (orderParams != null && orderParams.Length > 0)            {                for (int i = 0; i < orderParams.Length; i++)                {                    //根据属性名获取属性                    var _property = typeof(T).GetProperty(orderParams[i].PropertyName);                    //创建一个访问属性的表达式                    var _propertyAccess = Expression.MakeMemberAccess(_orderParames, _property);                    var _orderByExp = Expression.Lambda(_propertyAccess, _orderParames);                    string _orderName = orderParams[i].Method == OrderMethod.ASC ? "OrderBy" : "OrderByDescending";                    MethodCallExpression resultExp = Expression.Call(typeof(Queryable), _orderName, new Type[] { typeof(T), _property.PropertyType }, _list.Expression, Expression.Quote(_orderByExp));                    _list = _list.Provider.CreateQuery<T>(resultExp);                }            }            if (number > 0) _list = _list.Take(number);            return _list;        }        #endregion        //查找实体分页列表        #region FindPageList        /// <summary>        /// 查找分页列表        /// </summary>        /// <param name="pageSize">每页记录数。必须大于1</param>        /// <param name="pageIndex">页码。首页从1开始，页码必须大于1</param>        /// <param name="totalNumber">总记录数</param>        /// <returns></returns>        public IQueryable<T> FindPageList(int pageSize, int pageIndex, out int totalNumber)        {            OrderParam _orderParam = null;            return FindPageList(pageSize, pageIndex, out totalNumber, _orderParam);        }        /// <summary>        /// 查找分页列表        /// </summary>        /// <param name="pageSize">每页记录数。必须大于1</param>        /// <param name="pageIndex">页码。首页从1开始，页码必须大于1</param>        /// <param name="totalNumber">总记录数</param>        /// <param name="order">排序键</param>        /// <param name="asc">是否正序</param>        /// <returns></returns>        public IQueryable<T> FindPageList(int pageSize, int pageIndex, out int totalNumber, OrderParam orderParam)        {            return FindPageList(pageSize, pageIndex, out totalNumber, (T) => true, orderParam);        }        /// <summary>        /// 查找分页列表        /// </summary>        /// <param name="pageSize">每页记录数。必须大于1</param>        /// <param name="pageIndex">页码。首页从1开始，页码必须大于1</param>        /// <param name="totalNumber">总记录数</param>        /// <param name="where">查询表达式</param>        public IQueryable<T> FindPageList(int pageSize, int pageIndex, out int totalNumber, Expression<Func<T, bool>> where)        {            OrderParam _param = null;            return FindPageList(pageSize, pageIndex, out totalNumber, where, _param);        }        /// <summary>        /// 查找分页列表        /// </summary>        /// <param name="pageSize">每页记录数。</param>        /// <param name="pageIndex">页码。首页从1开始</param>        /// <param name="totalNumber">总记录数</param>        /// <param name="where">查询表达式</param>        /// <param name="orderParam">排序【null-不设置】</param>        /// <returns></returns>        public IQueryable<T> FindPageList(int pageSize, int pageIndex, out int totalNumber, Expression<Func<T, bool>> where, OrderParam orderParam)        {            OrderParam[] _orderParams = null;            if (orderParam != null) _orderParams = new OrderParam[] { orderParam };            return FindPageList(pageSize, pageIndex, out totalNumber, where, _orderParams);        }        /// <summary>        /// 查找分页列表        /// </summary>        /// <param name="pageSize">每页记录数。</param>        /// <param name="pageIndex">页码。首页从1开始</param>        /// <param name="totalNumber">总记录数</param>        /// <param name="where">查询表达式</param>        /// <param name="orderParams">排序【null-不设置】</param>        public IQueryable<T> FindPageList(int pageSize, int pageIndex, out int totalNumber, Expression<Func<T, bool>> where, OrderParam[] orderParams)        {            if (pageIndex < 1) pageIndex = 1;            if (pageSize < 1) pageSize = 10;            IQueryable<T> _list = DbContext.Set<T>().Where(where);            var _orderParames = Expression.Parameter(typeof(T), "o");            if (orderParams != null && orderParams.Length > 0)            {                for (int i = 0; i < orderParams.Length; i++)                {                    //根据属性名获取属性                    var _property = typeof(T).GetProperty(orderParams[i].PropertyName);                    //创建一个访问属性的表达式                    var _propertyAccess = Expression.MakeMemberAccess(_orderParames, _property);                    var _orderByExp = Expression.Lambda(_propertyAccess, _orderParames);                    string _orderName = orderParams[i].Method == OrderMethod.ASC ? "OrderBy" : "OrderByDescending";                    MethodCallExpression resultExp = Expression.Call(typeof(Queryable), _orderName, new Type[] { typeof(T), _property.PropertyType }, _list.Expression, Expression.Quote(_orderByExp));                    _list = _list.Provider.CreateQuery<T>(resultExp);                }            }            totalNumber = _list.Count();            return _list.Skip((pageIndex - 1) * pageSize).Take(pageSize);        }        #endregion        //添加实体        #region Add        /// <summary>        /// 添加实体【立即保存】        /// </summary>        /// <param name="entity">实体</param>        /// <returns>受影响的对象的数目</returns>        public int Add(T entity)        {            return Add(entity, true);        }        /// <summary>        /// 添加实体        /// </summary>        /// <param name="entity">实体</param>        /// <param name="isSave">是否立即保存</param>        /// <returns>在“isSave”为True时返回受影响的对象的数目，为False时直接返回0</returns>        public int Add(T entity, bool isSave)        {            DbContext.Set<T>().Add(entity);            return isSave ? DbContext.SaveChanges() : 0;        }        #endregion        //更新实体        #region Update        /// <summary>        /// 更新实体【立即保存】        /// </summary>        /// <param name="entity">实体</param>        /// <returns>受影响的对象的数目</returns>        public int Update(T entity)        {            return Update(entity, true);        }        /// <summary>        /// 更新实体        /// </summary>        /// <param name="entity">实体</param>        /// <param name="isSave">是否立即保存</param>        /// <returns>在“isSave”为True时返回受影响的对象的数目，为False时直接返回0</returns>        public int Update(T entity, bool isSave)        {            DbContext.Set<T>().Attach(entity);            DbContext.Entry<T>(entity).State = EntityState.Modified;            return isSave ? DbContext.SaveChanges() : 0;        }        #endregion        //删除        #region Delete        /// <summary>        /// 删除实体【立即保存】        /// </summary>        /// <param name="entity">实体</param>        /// <returns>受影响的对象的数目</returns>        public int Delete(T entity)        {            return Delete(entity, true);        }        /// <summary>        /// 删除实体        /// </summary>        /// <param name="entity">实体</param>        /// <param name="isSave">是否立即保存</param>        /// <returns>在“isSave”为True时返回受影响的对象的数目，为False时直接返回0</returns>        public int Delete(T entity, bool isSave)        {            DbContext.Set<T>().Attach(entity);            DbContext.Entry<T>(entity).State = EntityState.Deleted;            return isSave ? DbContext.SaveChanges() : 0;        }        /// <summary>        /// 批量删除实体        /// </summary>        /// <param name="entities">实体集合</param>        /// <returns>受影响的对象的数目</returns>        public int Delete(IEnumerable<T> entities)        {            DbContext.Set<T>().RemoveRange(entities);            return DbContext.SaveChanges();        }        #endregion        //记录数        #region Count        /// <summary>        /// 记录数        /// </summary>        /// <returns></returns>        public int Count()        {            return DbContext.Set<T>().Count();        }        /// <summary>        /// 记录数        /// </summary>        /// <param name="predicate">表达式</param>        /// <returns></returns>        public int Count(Expression<Func<T, bool>> predicate)        {            return DbContext.Set<T>().Count(predicate);        }        #endregion        /// <summary>        /// 记录是否存在        /// </summary>        /// <param name="predicate">表达式</param>        /// <returns></returns>        public bool IsContains(Expression<Func<T, bool>> predicate)        {            return Count(predicate) > 0;        }        /// <summary>        /// 保存数据【在Add、Upate、Delete未立即保存的情况下使用】        /// </summary>        /// <returns>受影响的记录数</returns>        public int Save()        {            return DbContext.SaveChanges();        }    }

/// <summary>    /// 排序参数    /// </summary>    public class OrderParam    {        /// <summary>        /// 属性名        /// </summary>        public string PropertyName { get; set; }        /// <summary>        /// 排序方式        /// </summary>        public OrderMethod Method { get; set; }    }    /// <summary>    /// 排序方式    /// </summary>    public enum OrderMethod    {        /// <summary>        /// 正序        /// </summary>        ASC,        /// <summary>        /// 倒序        /// </summary>        DESC    }