<?php
header("Content-type: text/html; charset=gb2312");
$pdo=new pdo("mysql:host=localhost;dbname=news;charset=gbk","root","");

class dosql{
     private $dbs=array(
      'host'=>'localhost',
      'user'=>'root',
      'pwd'=>'',
      'dbnames'=>'news',
      );

     private $pdo;
     private $datas;

     public function __construct(){
      $this->connect();
     }

     public function connect(){
      $host=$this->dbs['host'];
      $user=$this->dbs['user'];
      $pwd=$this->dbs['pwd'];
      $dbnames=$this->dbs['dbnames'];
  $this->pdo=new pdo("mysql:host=$host;dbname=$dbnames;charset=gbk","$user","");
     }

    public function datas($datas){
           $this->datas=$datas;
           //返回自己，方便链式调用
           return $this;
    }

     public function query($sql){
      //预处理，$sql-查询语句，$this->datas-参数数据
      $stmt=$this->pdo->prepare($sql);
      $stmt->execute($this->datas);
      
      var_dump($stmt);
      return $stmt;
     }
}

//使用示例
$mypdo=new dosql();
$sql="updates news set title=?,hit=? where id=?";
$mypdo->datas(array('gfgf','234','1'))->query($sql);

 ?>