public  function count(){
        $db=new Db();
        $db->connect();
        $query="select count(*) from wenzhang";
        $shuju=$db->query($query);
        $db->close();
        return $shuju;

    }

public function query($query)    //发送sql语句 insert update select
        {
            $this->result=mysql_query($query);
        }