MySQL数据库单例连接简单实现（MySQL扩展）

<?php
/**
 * MySQL数据库单例实现
 *
 * @author shizq at 2015-04-22
 *
 */
final class MySQLFactory {

	private static $instance;

	private function __construct() {}

	public static function getInstance($server, $uname, $passwd, $dbname) {
		if (! self::$instance) {
			self::$instance = mysql_connect($server, $uname, $passwd) or
			die('Error: ' . mysql_error());
			mysql_select_db($dbname, self::$instance) or
			die('Error: ' . mysql_error(self::$instance));
			mysql_set_charset('utf-8', self::$instance);
		}
		return self::$instance;
	}
}

$link = MySQLFactory::getInstance('localhost', 'root', '123456', 'test');