public function extToMimeType(string $ext_file): string
    {
        if ($ext_file && !preg_match('/^[a-z0-9_\-]+$/ui', $ext_file)) {
            $ext = $this->c::fileExt($ext_file);
        } else {
            $ext = $ext_file;
        }
        switch (($ext = mb_strtolower($ext))) {
            case 'svg':
                $type = 'image/svg+xml; charset=utf-8';
                break;

            case 'png':
                $type = 'image/png';
                break;

            case 'jpg':
                $type = 'image/jpeg';
                break;

            case 'gif':
                $type = 'image/gif';
                break;

            default:
                $type = $ext ? 'image/'.$ext : '';
        }
        return $type;
    }