/// <summary>
/// Initializes a new instance of the <see cref="GAF.Net.PacketHeader"/> class.
/// </summary>
/// <param name="headerBytes">Header bytes.</param>
public PacketHeader(byte[] headerBytes)
{
_headerBytes = headerBytes;
if (_headerBytes.Length != HeaderLength)
{
throw new ArgumentOutOfRangeException("headerBytes", string.Format("The header must be a byte array of length {0}", HeaderLength));
}
// header consists of
//soh (Guid) 16 bytes
//length (int) 4 bytes
//pid (byte) 1 byte
//oid (Guid) 16 bytes
var headerSoh = new byte[16]; //guid
var headerOid = new byte[16]; //guid
//get the header elements
Array.Copy(headerBytes, _indexOfSoh, headerSoh, 0, headerSoh.Length);
if (new Guid(headerSoh).ToString() != SOH.ToString())
{
throw new ArgumentException("SOH is invalid.", "headerBytes");
}
// pid
PacketId = (PacketId)headerBytes [_indexOfPid];
// objectId set by consumer
Array.Copy(headerBytes, _indexOfOid, headerOid, 0, headerOid.Length);
ObjectId = new Guid(headerOid);
DataLength = BitConverter.ToInt32(headerBytes, _indexofDataLengthElement);
}
/// <summary>
/// Returns the Packet as a byte array.
/// </summary>
/// <returns>A byte array.</returns>
public byte[] ToByteArray()
{
var headerBytes = new byte[HeaderLength];
var soh = SOH.ToByteArray();
var pid = new byte[1] {
(byte)PacketId
};
var headerObjectId = ObjectId.ToByteArray();
var headerDataLength = BitConverter.GetBytes(DataLength);
//copy the header elements to the header property
Array.Copy(soh, 0, headerBytes, _indexOfSoh, soh.Length); // SOH
Array.Copy(headerDataLength, 0, headerBytes, _indexofDataLengthElement, headerDataLength.Length); //Data Length
Array.Copy(pid, 0, headerBytes, _indexOfPid, pid.Length);
Array.Copy(headerObjectId, 0, headerBytes, _indexOfOid, headerObjectId.Length); // Object Id
return(headerBytes);
}
