/**
* 返回工厂实例，单例模式
*/
public static function factory($driver = null, $tableName = null)
{
//只实例化一个对象
if (is_null(self::$dbFactory)) {
self::$dbFactory = new dbFactory();
}
if (is_null($driver)) {
$driver = C("DB_DRIVER");
}
if (is_null($tableName)) {
$tableName = 'empty';
}
if (isset(self::$dbFactory->driver_list[$tableName])) {
return self::$dbFactory->driver_list[$tableName];
}
self::$dbFactory->getDriver($driver, $tableName);
return self::$dbFactory->driver_list[$tableName];
}
