JeroenDesloovere\VCard\VCard::setFilename PHP Method

    public function setFilename($value, $overwrite = true, $separator = '_')
    {
        // recast to string if $value is array
        if (is_array($value)) {
            $value = implode($separator, $value);
        }
        // trim unneeded values
        $value = trim($value, $separator);
        // remove all spaces
        $value = preg_replace('/\\s+/', $separator, $value);
        // if value is empty, stop here
        if (empty($value)) {
            return;
        }
        // decode value + lowercase the string
        $value = strtolower($this->decode($value));
        // urlize this part
        $value = Transliterator::urlize($value);
        // overwrite filename or add to filename using a prefix in between
        $this->filename = $overwrite ? $value : $this->filename . $separator . $value;
    }