/// <summary>
 /// 向数据库中添加一条记录
 /// </summary>
 /// <param name="model">要添加的实体</param>
 /// <returns>插入数据的ID</returns>
 public int Insert(TagImgRelationModel model)
 {
     #region SQL语句
     const string sql = @"
     INSERT INTO [dbo].[TagImgRelation] (
     [TagId]
     ,[ImgId]
     )
     VALUES (
     @TagId
     ,@ImgId
     );select @@IDENTITY";
     #endregion
     var res = SqlHelper.ExecuteScalar(sql,
             new SqlParameter("@TagId", model.TagId),
             new SqlParameter("@ImgId", model.ImgId)
         );
     return res == null ? 0 : Convert.ToInt32(res);
 }
 /// <summary>
 /// 根据主键ID更新一条记录
 /// </summary>
 /// <param name="model">更新后的实体</param>
 /// <returns>执行结果受影响行数</returns>
 public int Update(TagImgRelationModel model)
 {
     return _dao.Update(model);
 }
 /// <summary>
 /// 根据主键ID更新一条记录
 /// </summary>
 /// <param name="model">更新后的实体</param>
 /// <returns>执行结果受影响行数</returns>
 public int Update(TagImgRelationModel model)
 {
     #region SQL语句
     const string sql = @"
     UPDATE [dbo].[TagImgRelation]
     SET
     [TagId] = @TagId
     ,[ImgId] = @ImgId
     WHERE [RId] = @RId";
     #endregion
     return SqlHelper.ExecuteNonQuery(sql,
             new SqlParameter("@RId", model.RId),
             new SqlParameter("@TagId", model.TagId),
             new SqlParameter("@ImgId", model.ImgId)
         );
 }
 /// <summary>
 /// 向数据库中添加一条记录
 /// </summary>
 /// <param name="model">要添加的实体</param>
 /// <returns>插入数据的ID</returns>
 public int Insert(TagImgRelationModel model)
 {
     return _dao.Insert(model);
 }