Simple implementation of previous page and next page

Question

     $front=db('archives')->where("id>".$aid)->order('id asc')->limit('1')->find();//上一页        $this->assign('front',$front);//上一页
        $after=db('archives')->where("id<".$aid)->order('id desc')->limit('1')->find();//下一页        $this->assign('after',$after);//下一页

<div class="point">             <p>上一篇：<a href="{:url('Article/index',array('aid'=>$front['id']))}">{$front['title']}</a></p>            <p>下一篇：<a href="{:url('Article/index',array('aid'=>$after['id']))}">{$after['title']}</a></p> </div>

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