System.Net.FtpControlStream.FormatAddressV6 C# (CSharp) Method

        private string FormatAddressV6(IPAddress address, int port)
        {
            StringBuilder sb = new StringBuilder(43); // based on max size of IPv6 address + port + seperators
            String addressString = address.ToString();
            sb.Append("|2|");
            sb.Append(addressString);
            sb.Append('|');
            sb.Append(port.ToString(NumberFormatInfo.InvariantInfo));
            sb.Append('|');
            return sb.ToString();
        }