/**
     * 下劃線轉(zhuǎn)駝峰
     * @param $str
     * @return null|string|string[]
     */
    public static function lineToHump($str)
    {
        $str = preg_replace_callback('/([-_]+([a-z]{1}))/i', function ($matches) {
            return strtoupper($matches[2]);
        }, $str);
        return $str;
    }

    /**
     * 駝峰轉(zhuǎn)下劃線
     * @param $str
     * @return null|string|string[]
     */
    public static function humpToLine($str)
    {
        $str = preg_replace_callback('/([A-Z]{1})/', function ($matches) {
            return '_' . strtolower($matches[0]);
        }, $str);
        return $str;
    }