Am looking for C# open source NMEA parser.
Well, I'm not familiar with it myself, but some quick searches show one on CodeProject, which links to 2 other such, here and here. Any of those help?
check out sharpGPS . there are several other gps and nmea related projects o codeplex too
FWIW, it's not hard (10-40 LOC) to parse the basic ones your self. If you find you need to do this, here is a link with some useful info.
One more (support several devices) http://www.codeproject.com/Articles/279647/NMEA-sentence-parser-builder
Here is another open source library, but written in C++ .
https://code.google.com/p/avr-nmea-gps-library/
You can compile that as a DLL and invoke it from C#. This code was written for microcontrollers, with very little memory and processing power, making this code a very fast alternative.
来源：https://stackoverflow.com/questions/173497/c-sharp-open-source-nmea-parser