php分页类

<?php
//分页类

class page{
private $total_rows; //总条数
private $onepage_rows;//一页显示数量
private $total_page; //总页数
private $page_rows; //页码数量
private $start_id;//描述起始ID
private $end_id;//描述结束ID
private $desc = ''; //描述上一页,下一页
private $self_page; //当前页
private $url;

public function __construct($total,$onepage_rows=10,$page_rows=5,$desc=''){
$this->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'])){
$pagestr .= '<strong>'.$v['str'].'</strong>';
continue;
}
$pagestr .= "<a href='".$v['url']."'>".$v['str']."</a>";
}
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 $this->self_page > 1 ? '<a href="'.$this->url.'1">'.$this->desc['first'].'</a>':'';
}
//末页
public function last(){
return $this->self_page < $this->page_rows ? '<a href="'.$this->url.$this->page_rows.'">'.$this->desc['last'].'</a>':'';
}

//上一页
public function prev(){
return $this->self_page > 1 ? '<a href="'.$this->url.($this->self_page-1).'">'.$this->desc['prev'].'</a>':'';
}
//下一页
public function next(){
return $this->self_page < $this->total_page ? '<a href="'.$this->url.($this->self_page+1).'">'.$this->desc['next'].'</a>':'';
}
//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;
}

}

?>