一个非常实用的分页类

 <?php
/**
* 文件名: page.class.php
* 说明:  分页类
* 作者:  江  南
* 联系方式：email:[email protected]
*   
* 创建日期：2009-1-7
*/
class page {
var $perpage= 10;  //每页显示多少条记录数
var $total;    //总记录数
var $curpage = 1;  //当前页码
var $pages;    //总页数
var $offset;   //记录偏移量
var $filename;   //分页文件名称
var $pagename = 'page'; //分页时用来传递参数的变量 如:"$filename?page=$curpage"
var $keywords;

function page($total,$perpage,$filename,$pagename,$keys) {
  $this->total = intval($total);
  if(isset($perpage)) $this->perpage = $perpage;
  $this->pages = ceil($this->total / $this->perpage);
  $this->getcurpage();
  $this->offset = ($this->curpage-1)*$this->perpage;
  if(isset($pagename)) $this->pagename = $pagename;
  if(isset($filename)) {
   $this->filename = $filename;
  } else {
   $this->filename = $_SERVER['PHP_SELF'];
  }
  if(isset($keys)){
   $this->keywords = $keys;
  }else{
   $this->keywords = "";
  }
}
function getcurpage() {
  if(isset($_GET[$this->pagename])) $this->curpage = intval($_GET[$this->pagename]);
  if($this->curpage < 1) $this->curpage = 1;
  if($this->curpage > $this->pages) $this->curpage = $this->pages;
}

function getfirstpage() {
  if($this->curpage == 1) {
   return "首页";
  } else {
   return "<a href=/"{$this->getlink(1)}/">首页</a>";
  }
}
function getnextpage() {
  $nextpage = $this->curpage + 1;
  return "<a href=/"{$this->getlink($nextpage)}/">下一页</a>";
}
function getprepage() {
  $prepage = $this->curpage - 1;
  return "<a href=/"{$this->getlink($prepage)}/">上一页</a>";
}
 
function getlastpage() {
  if($this->curpage == $this->pages) {
   return "尾页";
  } else {
   return "<a href=/"{$this->getlink($this->pages)}/">尾页</a>";
  }
}

function getlink($param) {
  if(strpos($this->filename,'?')) {
   return $this->filename."&".$this->pagename."=".$param."&".key_words."=".$this->keywords;
  } else {
   return $this->filename."?".$this->pagename."=".$param."&".key_words."=".$this->keywords;
  }
}

function showpage() {
  $begin = $this->curpage - 4;
        $end = $this->curpage + 5;
        if($this->curpage<=4){
                $begin = 1;
                $end = 10;
        }
        if($this->curpage > $this->pages-10){
                $begin = $this->pages - 10;
                $end = $this->pages;
        }
        if($begin<1){
                $begin = 1;
        }
        if($end>$this->pages){
                $end = $this->pages;
        }
        if($this->total>$this->perpage) {
         $pagenav = $this->getfirstpage();
   if($this->curpage > 1) {
    $pagenav .=  $this->getprepage();
   }
   for($i = $begin; $i <= $end; $i++) {
    if($i == $this->curpage) {
     $pagenav .=  "$i"." ";
    } else {
     $pagenav .= "<a href=/"{$this->getlink($i)}/">[$i]</a>"." ";
    }
   } 
   if($this->curpage < $this->pages) {
    $pagenav .= $this->getnextpage();
    $pagenav .= $this->getlastpage();
   } 
        }
        return $pagenav;
}
}
?>