Windows.Storage.Streams.InMemoryRandomAccessStream.WriteAsync C# (CSharp) Méthode

		public extern IAsyncOperationWithProgress<uint, uint> WriteAsync([In] IBuffer buffer);
		public extern IAsyncOperation<bool> FlushAsync();

        public static async Task <byte[]> TranscodeImageFile(WriteableBitmap wb)
        {
            using (var ras = wb.PixelBuffer.AsStream().AsRandomAccessStream())
            {
                System.Diagnostics.Debug.WriteLine("1");
                BitmapDecoder decoder = await BitmapDecoder.CreateAsync(ras);

                System.Diagnostics.Debug.WriteLine("2");
                var memStream = new Windows.Storage.Streams.InMemoryRandomAccessStream();
                System.Diagnostics.Debug.WriteLine("3");
                BitmapEncoder encoder = await BitmapEncoder.CreateForTranscodingAsync(memStream, decoder);

                encoder.BitmapTransform.ScaledWidth  = 320;
                encoder.BitmapTransform.ScaledHeight = 240;

                System.Diagnostics.Debug.WriteLine("4");
                await encoder.FlushAsync();

                System.Diagnostics.Debug.WriteLine("5");
                var outbuff = new byte[memStream.Size];
                System.Diagnostics.Debug.WriteLine("6");
                await memStream.WriteAsync(outbuff.AsBuffer());

                System.Diagnostics.Debug.WriteLine("7");
                return(outbuff);
            }
        }