Linq 增删改查

public class WorkshopDAL
    {
        PlantDataClassesDataContext objPlantDataClassesDataContext = new PlantDataClassesDataContext();
        

        /// <summary>
        /// 在数据库中查询满足条件的车间信息
        /// </summary>
        /// <param name="strWerks"></param>
        /// <returns></returns>
        public List<WorkShop> Query(string strWerks)
        {
            //在表tbl_WorkshopInfo中查询出strWerks工厂下的所有车间,构造List<WorkShop>返回
            List<WorkShop> lstWorkShop = new List<WorkShop>();
            try
            {
                var workshop = (from m in objPlantDataClassesDataContext.tbl_WorkshopInfo
                                where m.Workshop_Werks.Equals(strWerks)
                                select m).ToList();
                if (workshop.Count == 0) return null;
                foreach (tbl_WorkshopInfo item in workshop)
                {
                    WorkShop objWorkShop = new WorkShop();
                    objWorkShop.Code = item.Workshop_WorkshopCode;
                    objWorkShop.Description = item.Workshop_WorkshopDes;
                    objWorkShop.Id = item.Workshop_Id;
                    
                    Plant objPlant = new Plant();
                    objPlant.Werks = item.Workshop_Werks;

                    objWorkShop.Plant = objPlant;
                    objWorkShop.RecordChangeTrace.CreateDate = item.Workshop_CreatedTime;
                    objWorkShop.RecordChangeTrace.CreateUserCode = item.Workshop_CreatedPerson;
                    objWorkShop.RecordChangeTrace.ModifyDate = item.Workshop_LastChangedTime;
                    objWorkShop.RecordChangeTrace.ModifyUserCode = item.Workshop_LastChangedPerson;

                    lstWorkShop.Add(objWorkShop);
                }

            }
            catch (Exception)
            {
                return null;
                //throw;
            } 
            return lstWorkShop;
        }

        /// <summary>
        /// 在数据库中插入车间信息
        /// </summary>
        /// <param name="lstWorkShop"></param>
        /// <returns></returns>
        public bool Insert(List<WorkShop> lstWorkShop)
        {
            //在同一事务中,将lstWorkShop中的车间信息插入表tbl_WorkshopInfo中
            //返回操作成功与否
            using (TransactionScope scope = new TransactionScope())
            {
                try
                {
                    foreach(WorkShop tem in lstWorkShop)
                    {
                        tbl_WorkshopInfo objTbl_WorkshopInfo = new tbl_WorkshopInfo() 
                        {
                         Workshop_CreatedPerson = tem.RecordChangeTrace.CreateUserCode,
                         Workshop_CreatedTime = tem.RecordChangeTrace.CreateDate,
                         Workshop_LastChangedPerson = tem.RecordChangeTrace.ModifyUserCode,
                         Workshop_LastChangedTime = tem.RecordChangeTrace.ModifyDate,
                         Workshop_Werks = tem.Plant.Werks,
                         Workshop_WorkshopCode = tem.Code,
                         Workshop_WorkshopDes = tem.Description
                        };
                         //objTbl_WorkshopInfo.Workshop_Id = tem.Id;
                         //objTbl_WorkshopInfo.Workshop_Werks = tem.Plant.Werks;
                         //objTbl_WorkshopInfo.Workshop_WorkshopDes = tem.Plant.WerksDes;
                         //objTbl_WorkshopInfo.Workshop_CreatedTime = new HelperManager().GetDBCurrentDateTime2();
                         //objTbl_WorkshopInfo.Workshop_CreatedPerson = User.UserName;
                         //objTbl_WorkshopInfo.Workshop_LastChangedPerson = User.UserName;
                         //objTbl_WorkshopInfo.Workshop_LastChangedTime = new HelperManager().GetDBCurrentDateTime2();

                         objPlantDataClassesDataContext.tbl_WorkshopInfo.InsertOnSubmit(objTbl_WorkshopInfo);
                    }
                    objPlantDataClassesDataContext.SubmitChanges();
                    scope.Complete();   
                }
                catch (Exception)
                {
                    return false;
                }
                return true;
            }
           
        }

        /// <summary>
        /// 在数据库中删除车间信息
        /// </summary>
        /// <param name="lstWorkShop"></param>
        /// <returns></returns>
        public bool Delete(List<WorkShop> lstWorkShop)
        {
            //在同一事务中,在表tbl_WorkshopInfo中删除lstWorkShop中的车间信息
            //返回操作成功与否
            using (TransactionScope scope = new TransactionScope())
            {
                try
                {
                    string sql = @"delete from tbl_WorkshopInfo where Workshop_Werks = {0} and Workshop_WorkshopCode = {1};
                                 ";
                    foreach (WorkShop tem in lstWorkShop)
                    {
                        objPlantDataClassesDataContext.ExecuteCommand(sql,tem.Plant.Werks,tem.Code);
                    }
                    scope.Complete();                    
                }
                catch (Exception)
                {
                    return false;
                }
                return true;
            }
        }

        /// <summary>
        /// 在数据库中更新车间信息
        /// </summary>
        /// <param name="lstWorkShop"></param>
        /// <returns></returns>
        public bool Update(List<WorkShop> lstWorkShop)
        {
            //在同一事务中,在表tbl_WorkshopInfo中更新lstWorkShop中的车间信息
            //返回操作成功与否
            using (TransactionScope scope = new TransactionScope())
            {
                try
                {
                    foreach (WorkShop tem in lstWorkShop)
                    {
                        tbl_WorkshopInfo objTbl_WorkshopInfo = objPlantDataClassesDataContext.tbl_WorkshopInfo.Where
                            (b => b.Workshop_Werks.Equals(tem.Plant.Werks) && b.Workshop_WorkshopCode.Equals(tem.Code)).First();
                        objTbl_WorkshopInfo.Workshop_WorkshopDes = tem.Description;
                        objTbl_WorkshopInfo.Workshop_CreatedTime = tem.RecordChangeTrace.CreateDate;
                        objTbl_WorkshopInfo.Workshop_CreatedPerson = tem.RecordChangeTrace.CreateUserCode;
                        objTbl_WorkshopInfo.Workshop_LastChangedPerson = tem.RecordChangeTrace.ModifyUserCode;
                        objTbl_WorkshopInfo.Workshop_LastChangedTime = tem.RecordChangeTrace.ModifyDate;

                        objPlantDataClassesDataContext.SubmitChanges();
                    }
                    scope.Complete();

                }
                catch (Exception)
                {
                    return false;
                    //throw;
                }
                return true;
 
            }
            
        }