/**
* 加载精确的ua词典和字段匹配的ua词典
* @param string $extract_ualist
* @param string $rough_ualist
*/
public static function getInstance($extract_ualist = '', $rough_ualist = '')
{
if (self::$_instance === null) {
self::$_instance = new UserAgent($extract_ualist, $rough_ualist);
}
return self::$_instance;
}
