Asp.net 页面返回到上一页面

 /// <summary>
        /// 提示错误信息！操作回滚！
        /// </summary>
        /// <param name="msg"></param>
        /// <param name="code"></param>
        public static void Show_Msg(string msg)
        {

            HttpContext.Current.Response.Write("<script>alert(\"" + msg + "\");history.back();</script>");
            HttpContext.Current.Response.End();

        }
        /// <summary>
        /// 提示成功信息！转向！
        /// </summary>
        /// <param name="msg"></param>
        /// <param name="url"></param>
        public static void Show_Msg(string msg, string url)
        {
            HttpContext.Current.Response.Write("<script>alert(\"" + msg + "\");location.href='" + url + "';</script>");
        }

 --------------调用
show_msg("参数错误","abc.aspx");

show_msg("提交成功","def.aspx");