async void OnLoaded(object sender, RoutedEventArgs e)
{
this.receiveSocket = new TcpListener(
IPAddress.Loopback, 8888);
this.receiveSocket.Start();
// Accept one incoming connection and open up a stream over it for reading.
using (var socket = await this.receiveSocket.AcceptSocketAsync())
using (var receiveStream = new NetworkStream(socket))
{
var sizeBuffer = new byte[sizeof(ulong)];
// We loop for as long as that connection works for us and we make no
// attempt to recover if we have a read failure or similar.
//
// Note - because BitmapDecoder.CreateAsync() can take a stream without
// having to specify a size, it seems like I can just feed the network
// stream here straight into my function CreateSoftwareBitmapFromStreamAsync
// but that won't work because BitmapDecoder wants a stream that it can
// seek which the NetworkStream here won't be. Hence, we read the image
// of the network into a MemoryStream and that means we need to know how
// much we need to read and that means writing the size of the image down
// the wire first.
while (true)
{
// Read the size of the incoming image from the stream.
var readCount = await receiveStream.ReadAsync(sizeBuffer, 0, sizeof(ulong));
if (readCount == sizeof(ulong))
{
// How big does the image say it is?
var imageSize = BitConverter.ToUInt64(sizeBuffer, 0);
// Make a memory stream that's big enough to store the incoming image.
using (var imageStream = new MemoryStream((int)imageSize))
{
// Copy from the network into that memory stream.
await RandomAccessStream.CopyAsync(
receiveStream.AsInputStream(),
imageStream.AsOutputStream(),
imageSize);
// Create an image source (this is a XAML thing) in order to be able
// to put the image on the screen.
var imageSource = await CreateSoftwareBitmapSourceFromStreamAsync(
imageStream.AsRandomAccessStream());
// We are not on the UI thread so need to switch to do this.
await this.Dispatcher.RunAsync(
CoreDispatcherPriority.Normal,
() =>
{
// And put the image on the screen.
ReplaceImageSoftwareBitmapSource(this.destImage, imageSource);
}
);
}
}
}
}
}
