total_rows = $total;
        $this->onepage_rows = $onepage_rows;
        $this->page_rows = $page_rows;
        $this->total_page = ceil($this->total_rows / $this->onepage_rows);
        $this->self_page = min(max((int)@$_GET['page'],1),$this->total_page);
        $this->start_id= ($this->self_page-1)*$this->onepage_rows+1;
        $this->end_id= min($this->self_page*$this->onepage_rows , $this->total_rows);
        $this->desc = $this->desc($desc); //上一页 下一页 共X条记录等信息
        $this->url = $this->requestUrl(); //URL生成
    }

    private function requestUrl(){
        $url =isset($_SERVER['REQUEST_URI']) ? $_SERVER['REQUEST_URI'] : $_SERVER['PHP_SELF'].'?'.$_SERVER['QUERY_STRING'] ;
        $parse_url = parse_url($url);
        if(isset($parse_url['query'])){
            parse_str($parse_url['query'],$arr);
            unset($arr['page']);
            $url =  $parse_url['path'] .'?'.http_build_query($arr).'&page=';
        }else{
            $url = strstr($url,'?') ?  $url.'page=' :$url. '?page=';
        }    
        return $url;
    }

    //指定列表页码
    public function pagelist(){  
        $start=max(1,min($this->self_page-ceil($this->page_rows/2),$this->total_page-$this->page_rows));
        $end=$start + $this->page_rows;
        $arr = array();
        for($i=$start; $i<=$end; $i++){
            if($i == $this->self_page){
                $arr[$i]['url'] = '';
                $arr[$i]['str'] = $i;
                continue;
            }
            $arr[$i]['url'] = $this->url.$i;
            $arr[$i]['str'] = $i;
        }
        return $arr;
    }

    //返回代码列表的字符串表示
    public function pageshow(){
        $pagelist = $this->pagelist();
        $pagestr = '';
        foreach($pagelist as $v){
            if(empty($v['url'])){
                $pagestr .= ''.$v['str'].'';
                continue;
            }
            $pagestr .= "".$v['str']."";
        }
        return $pagestr;
    }

    public function desc($desc){
        $d = array('prev' => '上一页','next' => '下一页','first'=> '首页','last' => '末页');
        if(empty($desc) || !is_array($desc)){ return $d;}
        function filter($v){
            return !empty($v);
        }
        return array_merge($d,array_filter($desc,'filter'));
    }
     //首页
    public function first(){
        return $this->self_page > 1 ? 'url.'1">'.$this->desc['first'].'':'';
    }     
    //末页
    public function last(){
        return $this->self_page < $this->page_rows ? 'url.$this->page_rows.'">'.$this->desc['last'].'':'';
    }

    //上一页
    public function prev(){
        return $this->self_page > 1 ? 'url.($this->self_page-1).'">'.$this->desc['prev'].'':'';
    }
    //下一页
    public function next(){
        return $this->self_page < $this->total_page ? 'url.($this->self_page+1).'">'.$this->desc['next'].'':'';
    }
    //返回当前第X-X条
    public function nowpage(){
        return '当前第'.$this->self_page.'页 第'.$this->start_id.'——'.$this->end_id.'条';
    }

    public function limit(){
        return 'limit '.max(0,($this->self_page-1)*$this->onepage_rows).','.$this->onepage_rows;
    }


}


 ?>