example-Geoid.cs

using System;
using NETGeographicLib;

namespace example_Geoid
{
    class Program
    {
        static void Main(string[] args)
        {
            try {
                Geoid egm96 = new Geoid("egm96-5", "", true, false);
                // Convert height above egm96 to height above the ellipsoid
                double lat = 42, lon = -75, height_above_geoid = 20;
                double
                    geoid_height = egm96.Height(lat, lon),
                    height_above_ellipsoid = (height_above_geoid +
                        (double)Geoid.ConvertFlag.GEOIDTOELLIPSOID * geoid_height);
                Console.WriteLine(height_above_ellipsoid);
            }
            catch (GeographicErr e) {
                Console.WriteLine(String.Format("Caught exception: {0}", e.Message));
            }
        }
    }
}