class getpage{

     public $pagenum;

     public $pagecontents;

     public $sql;

     public $url;

     public function __construct($a){

         $this->pagecontents = $a;

         $this->url = 'http://'.$_SERVER['HTTP_HOST'].$_SERVER['REQUEST_URI'];

     }

     //获取分页数

     public function createpage($sql){

         $this->sql = $sql;

         $conn = mysql_connect('localhost','root','root');

         if(!$conn){

             die(mysql_error());

         }

         mysql_select_db('class',$conn)or die(mysql_error());

         mysql_query("set names 'utf8'");

         $handle = mysql_query($sql);

         $row = array();

         while($r = mysql_fetch_row($handle)){

             $row[] = $r;

         }

         //假如除的结果为小数，则进1来保证分页数量

         $pagenum = count($row)/$this->pagecontents;

         $this->pagenum = ceil($pagenum);

     }

     //替换page参数

     private function replacestr(){

         if(isset($_GET['page'])){

             return str_replace("?page=".@$_GET['page'],"", $this->url);

         }else{

             @$_GET['page'] = 0;

         }

     }

     //页面分页显示

     public function createstyle(){

         for($i=0;$i<$this->pagenum;$i++){

             echo "<button><a href='".$this->replacestr($this->url)."?page=".$i*$this->pagecontents."'>".(1+$i)."</a></button>";

         }

     }

     public function getdata(){

         $where = " limit ".(@$_GET['page']).",".$this->pagecontents;

         $this->sql .= $where;

         $handle = mysql_query($this->sql);

         $arr = array();

         while($r = mysql_fetch_assoc($handle)){

             $arr[] = $r;

         }

         return $arr;

     }

 }