php+mysql，面向对象，查询

<code>    function __construct ($host,$root,$password){        $this->host     =$host;                                         $this->root     =$root;        $this->password =$password ;    }    function connect (){        @mysql_connect  ($this->host,$this->root,$this->password);        mysql_select_db ($this->database);        mysql_query     ("set names utf8");    }    function close(){        mysql_close();    }    function select(){        $result=mysql_query("select * from users");        print_r ($result);    }}    $link=new mysql("localhost","root","","stu_system");$link->connect();$link->select();$link->close();</code>