php 封装mysql类时出现的乱码问题

mysql_query("SET NAMES '$this->ut'")；出现乱码
mysql_query("SET NAMES 'GBK'")；不出现乱码

源代码
<?php

class mysql
{
private $host;
private $name;
private $pass;
private $db;
private $ut;

function __construct($host,$name,$pass,$db,$ut)
{
    $this->host=$host;
    $this->name=$name;
    $this->pass=$pass;
    $this->db=$db;
    $this->connect();
    $this->ut=$ut;
}

function connect()
{
 $link = mysql_connect($this->host,$this->name,$this->pass) or          die($this->error());
mysql_select_db($this->db,$link)or die("没有数据库:".$this->db);
mysql_query("set names '$this->ut'")；

}

function query($v)
{
    return mysql_query($v);

}
function error()
{
    return mysql_error();
}

function fn_insert($table,$name,$value )
{
    $this->query("insert into $table($name)value($value)");
}

}

$database = new mysql("localhost","root","","bbs","GBK");

$database->fn_insert
("message","id,user,title,content,lastdate","'','妈妈','标题是','内容是',now()");
?>