[Q]Packing messages into a byte buffer

[shofu_au]

Hi Group,

I am trying without much luck to pack messages into a byte buffer
using get and set accessors.

I have attached a simplified example of what I am trying to do using
byte variables.
(My real data is not byte variables.)

I wish to be able to populate a field in the message header and then
include this in a
init message, and finally once all the message is transfered to the
byte buffer populate
the message header length.

However I alway get zero for my message header length when I write to
the console.

I am confused I think with the get and set accessor.

Could anyone suggest where I have gone wrong.

Mark

using System;
using System.Collecti ons.Generic;
using System.Text;

namespace ConsoleApplicat ion1
{
class Program
{
static void Main(string[] args)
{
msgHdr msgHeader = new msgHdr();
// Don't set message length here.
msgHeader.messa geId = 100;

initMessage theInitrequest = new initMessage();
theInitrequest. messageHeader = msgHeader;
theInitrequest. version = 200;
//
// Hopefully here
// Initrequest.mes sageHeader.mess ageLength = 3
// Initrequest.mes sageHeader.mess ageId = 100
// Initrequest.ver sion = 200;

Console.WriteLi ne(theInitreque st.messageHeade r.messageLength .ToString());

Console.WriteLi ne(theInitreque st.messageHeade r.messageId.ToS tring());
Console.WriteLi ne(theInitreque st.version.ToSt ring());
// and
// Initrequest.Dat a [0] = 3
// Initrequest.Dat a [1] = 100;
// Initrequest.Dat a [2] = 200;
Console.WriteLi ne(theInitreque st.Data[0].ToString());
Console.WriteLi ne(theInitreque st.Data[1].ToString());
Console.WriteLi ne(theInitreque st.Data[2].ToString());

}
}
public class Utility
{
public static void Pack(byte src, ref byte[] Data, ref uint
Index)
{
Data[Index++] = src;
}

public static void Unpack(ref byte dst, byte[] Data, ref uint
Index)
{
dst = Data[Index++];
}
}

public class initMessage
{
public msgHdr messageHeader;
public byte version;

private byte[] _internalBuffer ;

public byte[] Data
{
set
{
uint index = 0;
Array.Copy(_int ernalBuffer, index, messageHeader.D ata,
0, messageHeader.D ata.Length);
index = index +
System.Convert. ToByte(messageH eader.Data.Leng th);
Utility.Unpack( ref version, value, ref index);
}
get
{
uint index = 0;
_internalBuffer = new byte[20];
Array.Copy(mess ageHeader.Data, 0, _internalBuffer ,
index, messageHeader.D ata.Length);
index = index +
System.Convert. ToByte(messageH eader.Data.Leng th);
Utility.Pack(ve rsion, ref _internalBuffer , ref index);
messageHeader.m essageLength =
System.Convert. ToByte(index);
return _internalBuffer ;
}
}
}

public class msgHdr
{
public byte messageLength;
public byte messageId;

private byte[] _internalBuffer = new byte[2];
public byte[] Data
{
set
{
uint index = 0;
Utility.Unpack( ref messageLength, value, ref index);
Utility.Unpack( ref messageId, value, ref index);
}
get
{
uint index = 0;
Utility.Pack(me ssageLength, ref _internalBuffer , ref
index);
Utility.Pack(me ssageId, ref _internalBuffer , ref
index);
return _internalBuffer ;
}
}
}
}