private static async Task <byte[]> ReadAsync(CancellationToken cancellationToken)
{
uint readBufferLength = 1024;
// If task cancellation was requested, comply
cancellationToken.ThrowIfCancellationRequested();
using (var reader = new DataReader(SerialPort.InputStream))
{
using (var cts = new CancellationTokenSource(5000))
{
// Set InputStreamOptions to complete the asynchronous read operation
// when one or more bytes is available
reader.InputStreamOptions = InputStreamOptions.Partial;
uint bytesRead = 0;
try
{
bytesRead = await reader.LoadAsync(readBufferLength).AsTask(cts.Token);
await ParentPage.Emr3ConnectionConnected(true);
if (bytesRead > 0)
{
byte[] buffer = new byte[bytesRead];
reader.ReadBytes(buffer);
reader.DetachStream();
return(buffer);
}
}
catch (TaskCanceledException e)
{
Debug.WriteLine("Task was cancelled after timeout");
Debug.WriteLine(e.Message);
await ParentPage.Emr3ConnectionConnected(false);
throw;
}
catch (Exception e)
{
Debug.WriteLine("Failed LoadAsync");
Debug.WriteLine(e.Message);
throw;
}
finally
{
reader.DetachStream();
}
}
return(new byte[0]);
}
}