public static async Task<byte[]> PackFileTransferMessageAsync(SongTransferMessage message)
{
byte[] serialized;
using (var ms = new MemoryStream())
{
using (var writer = new BsonWriter(ms))
{
var serializer = new JsonSerializer();
await Task.Run(() => serializer.Serialize(writer, message));
}
// Don't return earlier here, we don't know of the BsonWriter is finished.
serialized = ms.ToArray();
}
byte[] length = BitConverter.GetBytes(serialized.Length); // We have a fixed size of 4 bytes
var returnData = new byte[length.Length + serialized.Length];
// We could simply call .ToArray() everywhere, but with Buffer.BlockCopy, we are
// reducing memory pressure and CPU time on mobile devices by an order of magnitude
Buffer.BlockCopy(length, 0, returnData, 0, length.Length);
Buffer.BlockCopy(serialized, 0, returnData, length.Length, serialized.Length);
return returnData;
}
