从ArcObjects的ISpatialReference获取单位？

如何从ArcObjects中的ISpatialReference对象获取单位（米/英尺）？

仅当线性参考是投影坐标系时，才能从空间参考获得线性单位。因此，您需要将空间参考投射到IProjectedCoordinateSystem并访问其IProjectedCoordinateSystem.CoordinateUnit属性。

但是，如果空间参考是地理坐标系，则其单位是有角度的，并且可以通过IGeographicCoordinateSystem.CoordinateUnit进行类似访问。

IFields fields = featureClass.Fields;
        ISpatialReference spatialReference = fields.get_Field(fields.FindField(featureClass.ShapeFieldName)).GeometryDef.SpatialReference;
        if (spatialReference is IProjectedCoordinateSystem)
        {
            IProjectedCoordinateSystem projectedCoordinateSystem = (IProjectedCoordinateSystem)spatialReference;
            return projectedCoordinateSystem.CoordinateUnit.Name;
        }
        if (spatialReference is IGeographicCoordinateSystem)
        {
            IGeographicCoordinateSystem geographicCoordinateSystem = (IGeographicCoordinateSystem)spatialReference;
            return geographicCoordinateSystem.CoordinateUnit.Name;
        }