EF5 通用数据层 增删改查操作，泛型类(转）

using System;
using System.Collections.Generic;
using System.Data.Entity.Infrastructure;
using System.Linq;
using System.Linq.Expressions;
using System.Reflection;
using System.Text;
 
namespace P04DAL
{
    public class BaseDAL<T> where T:class,new()
    {
        /// <summary>
        /// 数据上下文对象
        /// </summary>
        P05MODEL.LeaveWordBoradEntities db = new P05MODEL.LeaveWordBoradEntities();
 
        #region 1.0 新增 实体 +int Add(T model)
        /// <summary>
        /// 新增 实体
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public int Add(T model)
        {
            db.Set<T>().Add(model);
            return db.SaveChanges();//保存成功后，会将自增的id设置给 model的 主键属性，并返回受影响行数
        }
        #endregion
 
        #region 2.0 根据 id 删除 +int Del(T model)
        /// <summary>
        /// 根据 id 删除
        /// </summary>
        /// <param name="model">包含要删除id的对象</param>
        /// <returns></returns>
        public int Del(T model)
        {
            db.Set<T>().Attach(model);
            db.Set<T>().Remove(model);
            return db.SaveChanges();
        }
        #endregion
 
        #region 3.0 根据条件删除 +int DelBy(Expression<Func<T, bool>> delWhere)
        /// <summary>
        /// 3.0 根据条件删除
        /// </summary>
        /// <param name="delWhere"></param>
        /// <returns></returns>
        public int DelBy(Expression<Func<T, bool>> delWhere)
        {
            //3.1查询要删除的数据
            List<T> listDeleting = db.Set<T>().Where(delWhere).ToList();
            //3.2将要删除的数据 用删除方法添加到 EF 容器中
            listDeleting.ForEach(u =>
            {
                db.Set<T>().Attach(u);//先附加到 EF容器
                db.Set<T>().Remove(u);//标识为 删除 状态
            });
            //3.3一次性 生成sql语句到数据库执行删除
            return db.SaveChanges();
        }
        #endregion
 
        #region 4.0 修改 +int Modify(T model, params string[] proNames)
        /// <summary>
        /// 4.0 修改，如：
        /// T u = new T() { uId = 1, uLoginName = "asdfasdf" };
        /// this.Modify(u, "uLoginName");
        /// </summary>
        /// <param name="model">要修改的实体对象</param>
        /// <param name="proNames">要修改的 属性 名称</param>
        /// <returns></returns>
        public int Modify(T model, params string[] proNames)
        {
            //4.1将 对象 添加到 EF中
            DbEntityEntry entry = db.Entry<T>(model);
            //4.2先设置 对象的包装 状态为 Unchanged
            entry.State = System.Data.EntityState.Unchanged;
            //4.3循环 被修改的属性名 数组
            foreach (string proName in proNames)
            {
                //4.4将每个 被修改的属性的状态 设置为已修改状态;后面生成update语句时，就只为已修改的属性 更新
                entry.Property(proName).IsModified = true;
            }
            //4.4一次性 生成sql语句到数据库执行
            return db.SaveChanges();
        }
        #endregion
 
        #region 4.0 批量修改 +int Modify(T model, Expression<Func<T, bool>> whereLambda, params string[] modifiedProNames)
        /// <summary>
        /// 4.0 批量修改
        /// </summary>
        /// <param name="model">要修改的实体对象</param>
        /// <param name="whereLambda">查询条件</param>
        /// <param name="proNames">要修改的 属性 名称</param>
        /// <returns></returns>
        public int ModifyBy(T model, Expression<Func<T, bool>> whereLambda, params string[] modifiedProNames)
        {
            //4.1查询要修改的数据
            List<T> listModifing = db.Set<T>().Where(whereLambda).ToList();
 
            //获取 实体类 类型对象
            Type t = typeof(T); // model.GetType();
            //获取 实体类 所有的 公有属性
            List<PropertyInfo> proInfos = t.GetProperties(BindingFlags.Instance | BindingFlags.Public).ToList();
            //创建 实体属性 字典集合
            Dictionary<string, PropertyInfo> dictPros = new Dictionary<string, PropertyInfo>();
            //将 实体属性 中要修改的属性名 添加到 字典集合中 键：属性名  值：属性对象
            proInfos.ForEach(p =>
            {
                if (modifiedProNames.Contains(p.Name))
                {
                    dictPros.Add(p.Name, p);
                }
            });
 
            //4.3循环 要修改的属性名
            foreach (string proName in modifiedProNames)
            {
                //判断 要修改的属性名是否在 实体类的属性集合中存在
                if (dictPros.ContainsKey(proName))
                {
                    //如果存在，则取出要修改的 属性对象
                    PropertyInfo proInfo = dictPros[proName];
                    //取出 要修改的值
                    object newValue = proInfo.GetValue(model, null); //object newValue = model.uName;
 
                    //4.4批量设置 要修改 对象的 属性
                    foreach (T usrO in listModifing)
                    {
                        //为 要修改的对象 的 要修改的属性 设置新的值
                        proInfo.SetValue(usrO, newValue, null); //usrO.uName = newValue;
                    }
                }
            }
            //4.4一次性 生成sql语句到数据库执行
            return db.SaveChanges();
        }
        #endregion
 
        #region 5.0 根据条件查询 +List<T> GetListBy(Expression<Func<T,bool>> whereLambda)
        /// <summary>
        /// 5.0 根据条件查询 +List<T> GetListBy(Expression<Func<T,bool>> whereLambda)
        /// </summary>
        /// <param name="whereLambda"></param>
        /// <returns></returns>
        public List<T> GetListBy(Expression<Func<T, bool>> whereLambda)
        {
            return db.Set<T>().Where(whereLambda).ToList();
        }
        #endregion
 
        #region 5.1 根据条件 排序 和查询 + List<T> GetListBy<TKey>
        /// <summary>
        /// 5.1 根据条件 排序 和查询
        /// </summary>
        /// <typeparam name="TKey">排序字段类型</typeparam>
        /// <param name="whereLambda">查询条件 lambda表达式</param>
        /// <param name="orderLambda">排序条件 lambda表达式</param>
        /// <returns></returns>
        public List<T> GetListBy<TKey>(Expression<Func<T, bool>> whereLambda, Expression<Func<T, TKey>> orderLambda)
        {
            return db.Set<T>().Where(whereLambda).OrderBy(orderLambda).ToList();
        }
        #endregion
 
        #region 6.0 分页查询 + List<T> GetPagedList<TKey>
        /// <summary>
        /// 6.0 分页查询 + List<T> GetPagedList<TKey>
        /// </summary>
        /// <param name="pageIndex">页码</param>
        /// <param name="pageSize">页容量</param>
        /// <param name="whereLambda">条件 lambda表达式</param>
        /// <param name="orderBy">排序 lambda表达式</param>
        /// <returns></returns>
        public List<T> GetPagedList<TKey>(int pageIndex, int pageSize, Expression<Func<T, bool>> whereLambda, Expression<Func<T, TKey>> orderBy)
        {
            // 分页 一定注意： Skip 之前一定要 OrderBy
            return db.Set<T>().Where(whereLambda).OrderBy(orderBy).Skip((pageIndex - ) * pageSize).Take(pageSize).ToList();
        }
        #endregion
    }
}