internal void WriteSecondHeader(BitWriter writer, int id)
{
// compute the minimum number of bytes necessary to encode the handle
var handleBytes = BitConverter.GetBytes(HandleOrOffset);
if (BitConverter.IsLittleEndian)
{
Array.Reverse(handleBytes);
}
var bytesList = new List <byte>(handleBytes);
while (bytesList.Count > 0 && bytesList[0] == 0)
{
bytesList.RemoveAt(0);
}
if (bytesList.Count == 0)
{
// ensure there's a least one byte
bytesList.Add(0);
}
writer.Write_RC((byte)bytesList.Count);
writer.Write_RC((byte)id);
writer.WriteBytes(bytesList.ToArray());
}
internal void Write(BitWriter writer, int offsetAdjustment)
{
var startOffset = writer.Position;
writer.WriteBytes(StartSentinel);
var imageCount = 0;
if (HeaderData?.Length > 0)
{
imageCount++;
}
if (BmpData?.Length > 0)
{
imageCount++;
}
if (WmfData?.Length > 0)
{
imageCount++;
}
var imageControlByteCount =
imageCount * (1 + 4 + 4) + // each set of data writes a byte and two ints
1; // `imageCount` below
var overallSize =
imageControlByteCount +
(HeaderData?.Length ?? 0) +
(BmpData?.Length ?? 0) +
(WmfData?.Length ?? 0);
writer.Write_RL(overallSize);
writer.Write_RC((byte)imageCount);
if (HeaderData?.Length > 0)
{
writer.Write_RC(1);
writer.Write_RL(writer.Position - startOffset + offsetAdjustment); // start
writer.Write_RL(HeaderData.Length);
}
if (BmpData?.Length > 0)
{
writer.Write_RC(2);
writer.Write_RL(writer.Position - startOffset + offsetAdjustment); // start
writer.Write_RL(BmpData.Length);
}
if (WmfData?.Length > 0)
{
writer.Write_RC(3);
writer.Write_RL(writer.Position - startOffset + offsetAdjustment); // start
writer.Write_RL(WmfData.Length);
}
writer.WriteBytes(EndSentinel);
}