C# Definition:

[StructLayout(LayoutKind.Explicit, Size = 28)]

    internal struct sockaddr_in6
    [StructLayout(LayoutKind.Explicit, Size = 16)]
    public struct in6_addr
    {
        [FieldOffset(0)] internal ADDRESS_FAMILIES sin6_family;
        [FieldOffset(2)] internal ushort sin6_port;
        [FieldOffset(4)] internal uint sin6_flowinfo;
        [FieldOffset(8)] internal in6_addr sin6_addr;
        [FieldOffset(24)] internal uint sin6_scope_id;
        [FieldOffset(0)]
        public byte Byte_0;
        [FieldOffset(1)]
        public byte Byte_1;
        [FieldOffset(2)]
        public byte Byte_2;
        [FieldOffset(3)]
        public byte Byte_3;

        internal string Host
        {
        get
        {
            var local = this;
            var length = (uint) 256;
            var builder = new StringBuilder((int) length);
        [FieldOffset(4)]
        public byte Byte_4;
        [FieldOffset(5)]
        public byte Byte_5;
        [FieldOffset(6)]
        public byte Byte_6;
        [FieldOffset(7)]
        public byte Byte_7;

            var data = new WSAData();
            WSAStartup(2, ref data);
            WSAAddressToString(ref local, (uint) Marshal.SizeOf(local), IntPtr.Zero, builder,
                          ref length);
            WSACleanup();
        [FieldOffset(8)]
        public byte Byte_8;
        [FieldOffset(9)]
        public byte Byte_9;
        [FieldOffset(10)]
        public byte Byte_10;
        [FieldOffset(11)]
        public byte Byte_11;

            return builder.ToString().Split(':')[0];
        }
        [FieldOffset(12)]
        public byte Byte_12;
        [FieldOffset(13)]
        public byte Byte_13;
        [FieldOffset(14)]
        public byte Byte_14;
        [FieldOffset(15)]
        public byte Byte_16;

        }
        [FieldOffset(0)]
        public short Word_0;
        [FieldOffset(2)]
        public short Word_1;
        [FieldOffset(4)]
        public short Word_2;
        [FieldOffset(6)]
        public short Word_3;

        internal string Port
        {
        get
        {
            var local = this;
            var length = (uint) 256;
            var builder = new StringBuilder((int) length);
        [FieldOffset(8)]
        public short Word_4;
        [FieldOffset(10)]
        public short Word_5;
        [FieldOffset(12)]
        public short Word_6;
        [FieldOffset(14)]
        public short Word_7;
    }
    [StructLayout(LayoutKind.Explicit, Size = 28)]
    public struct sockaddr_in6
    {
        [FieldOffset(0)]
        public ADDRESS_FAMILIES sin6_family;

            var data = new WSAData();
            WSAStartup(2, ref data);
            WSAAddressToString(ref local, (uint) Marshal.SizeOf(local), IntPtr.Zero, builder,
                          ref length);
            WSACleanup();
        [FieldOffset(2)]
        public ushort sin6_port;

            return builder.ToString().Split(':')[1];
        }
        [FieldOffset(4)]
        public uint sin6_flowinfo;

        }
        [FieldOffset(8)]
        public in6_addr sin6_addr;

        internal static sockaddr_in6 FromString(string host, int port)
        {
        var sockaddr = new sockaddr_in6();
        var lpAddressLength = Marshal.SizeOf(sockaddr);
        WSAStringToAddress(host + ":" + port, EnumLib.ADDRESS_FAMILIES.AF_INET6, IntPtr.Zero,
                          ref sockaddr, ref lpAddressLength);
        return sockaddr;
        }
        [FieldOffset(24)]
        public uint sin6_scope_id;
    }

VB Definition:

Structure sockaddr_in6
Public TODO
End Structure

User-Defined Field Types:

None.

    [StructLayout(LayoutKind.Explicit, Size = 28)]
    internal struct sockaddr_in6_UNSAFE
    {
        [FieldOffset(0)] internal EnumLib.ADDRESS_FAMILIES sin6_family;
        [FieldOffset(2)] internal ushort sin6_port;
        [FieldOffset(4)] internal uint sin6_flowinfo;
        [FieldOffset(8)] internal in6_addr sin6_addr;
        [FieldOffset(24)] internal uint sin6_scope_id;

Notes:

None.

        internal string Host
        {
        get
        {
            var local = this;
            var length = (uint) 256;
            var builder = new StringBuilder((int) length);

            var data = new WSAData();
            WSAStartup(2, ref data);
            WSAAddressToString(ref local, (uint) Marshal.SizeOf(local), IntPtr.Zero, builder,
                          ref length);
            WSACleanup();

            return builder.ToString().Split(':')[0];
        }

        }

        internal string Port
        {
        get
        {
            var local = this;
            var length = (uint) 256;
            var builder = new StringBuilder((int) length);

            var data = new WSAData();
            WSAStartup(2, ref data);
            WSAAddressToString(ref local, (uint) Marshal.SizeOf(local), IntPtr.Zero, builder,
                          ref length);
            WSACleanup();

            return builder.ToString().Split(':')[1];
        }

        }

        internal static sockaddr_in6 FromString(string host, int port)
        {
        var sockaddr = new sockaddr_in6();
        var lpAddressLength = Marshal.SizeOf(sockaddr);
        WSAStringToAddress(host + ":" + port, EnumLib.ADDRESS_FAMILIES.AF_INET6, IntPtr.Zero,
                          ref sockaddr, ref lpAddressLength);
        return sockaddr;
        }
    }