PHPMailer::quotedString( string $str ): string

5147    public static function quotedString($str)5148    {5149        if (preg_match('/[ ()<>@,;:"\/\[\]?=]/', $str)) {5150            //If the string contains any of these chars, it must be double-quoted5151            //and any double quotes must be escaped with a backslash5152            return '"' . str_replace('"', '\\"', $str) . '"';5153        }5154 5155        //Return the string untouched, it doesn't need quoting5156        return $str;5157    }