There's no out-of-the-box support for this today (it's on our backlog). However, you could intercept the NMEA stream with a stream interceptor class. For example:
public class StreamInterceptor : Stream
{
private readonly Stream _baseStream;
public StreamInterceptor(Stream baseStream)
{
_baseStream = baseStream;
}
public event EventHandler<string>? OnData;
public override int Read(byte[] buffer, int offset, int count)
{
int read = _baseStream.Read(buffer, offset, count);
if (read > 0)
{
OnData?.Invoke(this, Encoding.UTF8.GetString(buffer, 0, read));
}
return read;
}
public override bool CanRead => _baseStream.CanRead;
public override bool CanSeek => _baseStream.CanSeek;
public override bool CanWrite => _baseStream.CanWrite;
public override long Length => _baseStream.Length;
public override long Position { get => _baseStream.Position; set => _baseStream.Position = value; }
public override void Flush() => _baseStream.Flush();
public override long Seek(long offset, SeekOrigin origin) => _baseStream.Seek(offset, origin);
public override void SetLength(long value) => _baseStream.SetLength(value);
public override void Write(byte[] buffer, int offset, int count) => _baseStream.Write(buffer, offset, count);
}
Then you could create the nmea datasource using this new stream type and listen to the OnData event:
SerialPort p = new SerialPort("COM3");
NmeaLocationDataSource ds = NmeaLocationDataSource.FromStreamCreator(
onStart: (ds) =>
{
p.Open();
var sl = new StreamInterceptor(p.BaseStream);
sl.OnData += (s, nmeaString) =>
{
Console.Write(nmeaString); // NMEA raw data string
};
return Task.FromResult<System.IO.Stream>(sl);
},
onStop: (ds) =>
{
p.Close();
return Task.CompletedTask;
}
);
ds.StartAsync();
