mysql 分页处理

 /**
     *    获取分页信息
     *
     *
     * @return    array
     */
    function _get_page($page_per = 20)
    {
        $page = request('page', 'intval', 1);
        if ($page <= 0) {
            $page = 1;        //在商品列表输入00的话就报错
        }
        $start = ($page - 1) * $page_per;

        return array('limit' => "{$start},{$page_per}", 'curr_page' => $page, 'pageper' => $page_per);
    }