php构造函数连接数据库

require_once("mysql.config.php");
require_once("mysql.class.php");

echo $data->f();

<?php
/*
* Time 2014-03-31
* Author Sky
* 数据库基本信息
*/
$arr = include('../Cache/config.php');        //  连接 Yourphp的配置文件

$db_host = $arr['DB_HOST'];
$db_name = $arr['DB_NAME'];
$db_user = $arr['DB_USER'];
$db_pwd = $arr['DB_PWD'];
$db_preefix = $arr['DB_PREFIX'];

?>

<?php
class Data{
public $DB_HOST;
public $DB_NAME;
public $DB_USER;
public $DB_PWD;
public $DB_PREFIX;

function __construct($DB_HOST,$DB_NAME,$DB_USER,$DB_PWD,$DB_PREFIX){
$this->DB_HOST = $DB_HOST;
$this->DB_NAME = $DB_NAME;
$this->DB_USER = $DB_USER;
$this->DB_PWD = $DB_PWD;
$this->DB_PREFIX = $DB_PREFIX;

//***  连接数据库
$con = mysql_connect($DB_HOST,$DB_USER,$DB_PWD);
if (!$con)
{
die('数据库连接失败' . mysql_error());
}
mysql_select_db($DB_NAME, $con);
mysql_query('set names utf8');
}

function insert(){
echo '111';
}

}
$data = new Data($db_host,$db_name,$db_user,$db_pwd,$db_preefix);
?>