问NetTopologySuite.Core 1.15.3和距离单位

EN

        return new PagedList<Dto.DrugConsortium.CollectionSiteWithCoordinatesDto>(query.Select(p =>
            new Dto.DrugConsortium.CollectionSiteWithCoordinatesDto { CollectionSite = p, Distance = p.Location.ProjectTo(2855).Distance(myLocation) }).ToList(), pageIndex, pageSize);

public static class GeometryExtensions
{
    static readonly IGeometryServices _geometryServices = NtsGeometryServices.Instance;
    static readonly ICoordinateSystemServices _coordinateSystemServices
        = new CoordinateSystemServices(
            new CoordinateSystemFactory(),
            new CoordinateTransformationFactory(),
            new Dictionary<int, string>
            {
            // Coordinate systems:

            // (3857 and 4326 included automatically)

            // This coordinate system covers the area of our data.
            // Different data requires a different coordinate system.
            [2855] =
                @"
                PROJCS[""NAD83(HARN) / Washington North"",
                    GEOGCS[""NAD83(HARN)"",
                        DATUM[""NAD83_High_Accuracy_Regional_Network"",
                            SPHEROID[""GRS 1980"",6378137,298.257222101,
                                AUTHORITY[""EPSG"",""7019""]],
                            AUTHORITY[""EPSG"",""6152""]],
                        PRIMEM[""Greenwich"",0,
                            AUTHORITY[""EPSG"",""8901""]],
                        UNIT[""degree"",0.01745329251994328,
                            AUTHORITY[""EPSG"",""9122""]],
                        AUTHORITY[""EPSG"",""4152""]],
                    PROJECTION[""Lambert_Conformal_Conic_2SP""],
                    PARAMETER[""standard_parallel_1"",48.73333333333333],
                    PARAMETER[""standard_parallel_2"",47.5],
                    PARAMETER[""latitude_of_origin"",47],
                    PARAMETER[""central_meridian"",-120.8333333333333],
                    PARAMETER[""false_easting"",500000],
                    PARAMETER[""false_northing"",0],
                    UNIT[""metre"",1,
                        AUTHORITY[""EPSG"",""9001""]],
                    AUTHORITY[""EPSG"",""2855""]]
            "
            });

    public static IGeometry ProjectTo(this IGeometry geometry, int srid)
    {
        var geometryFactory = _geometryServices.CreateGeometryFactory(srid);
        var transformation = _coordinateSystemServices.CreateTransformation(geometry.SRID, srid);

        return GeometryTransform.TransformGeometry(
            geometryFactory,
            geometry,
            transformation.MathTransform);
    }
}