添加新增 删除旧的 避免id自增过多

    /// <summary>
        ///  编辑关联分类 的属性 添加新值删除去掉的值
        /// </summary>
        /// <param name="IListNew">最新的分类信息</param>
        /// <returns>是否更新成功</returns>
        public bool Update(IList<CategoryAttributeInfo> IListNew, int categoryID)
        {
            IList<CategoryAttributeInfo> IListOld = new List<CategoryAttributeInfo>();//取出数据库里的分类
            IList<CategoryAttributeInfo> IListDel = new List<CategoryAttributeInfo>();//待删除的
            IList<CategoryAttributeInfo> IListAdd = new List<CategoryAttributeInfo>();//待添加的

            IListOld = GetCategoryAttributeInfoList("CategoryID=" + categoryID, "");


            //对比取出 那些该删除 那些该添加
            foreach (CategoryAttributeInfo iListOld in IListOld)
            {
                if (IListNew.Contains(iListOld))
                {
                    IListNew.Remove(iListOld);
                }
                else
                {
                    IListDel.Add(iListOld);
                }

            }
            IListAdd = IListNew;

            using (SqlTransaction sqlTran = SqlHelper.BeginTransaction())
            {
                try
                {
                    foreach (CategoryAttributeInfo CategoryAttributeInfo in IListDel)
                    {
                        SqlHelper.ExecuteNonQuery(sqlTran, "delete  from t_CategoryAttribute where ID=" + CategoryAttributeInfo.ID, null);
                    }

                    //添加新增的 分类属性
                    foreach (CategoryAttributeInfo CategoryAttributeInfo in IListAdd)
                    {
                        Add(CategoryAttributeInfo);
                    }

                    sqlTran.Commit();
                    return true;

                }
                catch
                {
                    sqlTran.Rollback();
                    return false;
                }
            }

        }