linq to sql DAL

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Data.Linq;
namespace DAL{    public class LinQBaseDao    {        /// <summary>        /// 查询所有的记录        /// </summary>        /// <typeparam name="T"></typeparam>        /// <param name="dc"></param>        /// <returns></returns>        public IEnumerable<T> Query<T>(DataContext dc) where T:class        {            return dc.GetTable<T>().AsEnumerable<T>() ;        }        /// <summary>        /// 按条件查询记录        /// </summary>        /// <typeparam name="T"></typeparam>        /// <param name="dc"></param>        /// <param name="fun"></param>        /// <returns></returns>        public IEnumerable<T> Query<T>(DataContext dc, Func<T,bool> fun) where T : class         {            return dc.GetTable<T>().Where<T>(fun).AsEnumerable<T>();         }
        /// <summary>        /// 查询单条 返回实体        /// </summary>        /// <typeparam name="T"></typeparam>        /// <param name="fun"></param>        /// <returns></returns>        public T Single<T>(DataContext dc,Func<T, bool> fun) where T : class         {            return dc.GetTable<T>().Single<T>(fun);        }
        /// <summary>        /// 添加一条记录        /// </summary>        /// <typeparam name="T"></typeparam>        /// <param name="dc"></param>        /// <param name="tentity"></param>        public void InsertOne<T>(DataContext dc, T tentity) where T : class         {            var table = dc.GetTable<T>();            table.InsertOnSubmit(tentity);            dc.SubmitChanges();        }
        /// <summary>        /// 添加多条记录        /// </summary>        /// <typeparam name="T"></typeparam>        /// <param name="dc"></param>        /// <param name="tentitys"></param>        public void InsertToMany<T>(DataContext dc, IEnumerable<T> tentitys) where T : class         {            var table = dc.GetTable<T>();            table.InsertAllOnSubmit(tentitys);            dc.SubmitChanges();        }
        /// <summary>        /// 删除单条数据        /// </summary>        /// <typeparam name="T"></typeparam>        /// <param name="dc"></param>        /// <param name="tentity"></param>        /// <param name="fun"></param>        public void DeleteOne<T>(DataContext dc, T tentity, Func<T, bool> fun) where T : class         {            var table = dc.GetTable<T>();            var result = table.Where<T>(fun).First<T>();            table.DeleteOnSubmit(result);            dc.SubmitChanges();        }        /// <summary>        /// 按条件删除多条数据        /// </summary>        /// <typeparam name="T"></typeparam>        /// <param name="dc"></param>        /// <param name="tentitys"></param>        /// <param name="fun"></param>        public void DeleteToMany<T>(DataContext dc, IEnumerable<T> tentitys, Func<T, bool> fun) where T : class         {            var table = dc.GetTable<T>();            var result = table.Where<T>(fun).AsEnumerable<T>();            table.DeleteAllOnSubmit<T>(result);            dc.SubmitChanges();        }
        /// <summary>        /// 删除多条数据        /// </summary>        /// <typeparam name="T"></typeparam>        /// <param name="dc"></param>        /// <param name="tentitys"></param>        public void DeleteToManyByCondition<T>(DataContext dc, IEnumerable<T> tentitys) where T : class         {            var table = dc.GetTable<T>();            table.DeleteAllOnSubmit<T>(tentitys);            dc.SubmitChanges();        }
        /// <summary>        /// LINQ更新方法        /// </summary>        /// <typeparam name="T"></typeparam>        /// <param name="dc"></param>        /// <param name="fun"></param>        /// <param name="tentity"></param>        /// <param name="action"></param>        public void Update<T>(DataContext dc, Func<T, bool> fun, T tentity, Action<T> action) where T : class         {            var table = dc.GetTable<T>().Single<T>(fun);            //var table = dc.GetTable<T>().Where<T>(fun).Single<T>();            action(table);            dc.SubmitChanges();        }    }}