private void Run()
{
try
{
string workingBuffer = string.Empty;
while (true)
{
int bytesToRead = _port.BytesToRead;
if (bytesToRead > 0)
{
byte[] buffer = new byte[bytesToRead];
_port.Read(buffer, 0, buffer.Length);
string text = new string(Encoding.UTF8.GetChars(buffer));
workingBuffer += text.ToString();
int sentenceEndIndex;
while ((sentenceEndIndex = workingBuffer.IndexOf(CrLf)) != -1)
{
string sentence = workingBuffer.Substring(0, sentenceEndIndex);
if (sentence.IndexOf('$') != -1)
{
IGPSMessage message = GPSMessageParser.Parse(sentence);
if (message != null)
{
if (message is FixedDataMessage)
{
GPSPosition position = ParsePosition(message as FixedDataMessage);
if (PositionReceived != null)
{
PositionReceived(this, position);
}
}
}
}
if (sentenceEndIndex + CrLf.Length == workingBuffer.Length)
{
workingBuffer = string.Empty;
}
else
{
workingBuffer = workingBuffer.Substring(sentenceEndIndex + CrLf.Length, workingBuffer.Length - sentenceEndIndex - CrLf.Length);
}
sentenceEndIndex = workingBuffer.IndexOf(CrLf);
}
Thread.Sleep(100);
}
}
}
catch (ThreadAbortException)
{
}
}
private GPSPosition ParsePosition(FixedDataMessage message)
{
GPSPosition position = new GPSPosition();
position.HasFix = (message.PositionFix != PositionFixIndicator.Invalid);
position.IsEstimate = (message.PositionFix == PositionFixIndicator.Estimated);
if (position.HasFix)
{
position.Latitude = Convert.ToDouble(message.Latitude.Substring(0, 2)) + (Convert.ToDouble(message.Latitude.Substring(2, 7)) / 60);
if (message.NSIndicator == 'S')
position.Latitude = -position.Latitude;
position.Longitude = Convert.ToDouble(message.Longitude.Substring(0, 3)) + (Convert.ToDouble(message.Longitude.Substring(3, 7)) / 60);
if (message.EWIndicator == 'W')
position.Longitude = -position.Longitude;
}
return position;
}
private GPSPosition ParsePosition(FixedDataMessage message)
{
GPSPosition position = new GPSPosition();
position.HasFix = (message.PositionFix != PositionFixIndicator.Invalid);
position.IsEstimate = (message.PositionFix == PositionFixIndicator.Estimated);
if (position.HasFix)
{
position.Latitude = Convert.ToDouble(message.Latitude.Substring(0, 2)) + (Convert.ToDouble(message.Latitude.Substring(2, 7)) / 60);
if (message.NSIndicator == 'S')
{
position.Latitude = -position.Latitude;
}
position.Longitude = Convert.ToDouble(message.Longitude.Substring(0, 3)) + (Convert.ToDouble(message.Longitude.Substring(3, 7)) / 60);
if (message.EWIndicator == 'W')
{
position.Longitude = -position.Longitude;
}
}
return(position);
}
