C# SqlGeography从multipolygon获取多边形

我有一个表

Town

，其中列

townbound

包含相关城镇的多边形（

geography

datatype）

对于每个城镇，我都会获得生成KML（XML）文件所需的多边形数据，如：

sqlg = SqlGeography.STPolyFromText(new SqlChars(
town.TownBoundary.WellKnownValue.WellKnownText),
town.TownBoundary.CoordinateSystemId);
for (int i = 1; i <= sqlg.STNumPoints(); i++)
{
    SqlGeography point = sqlg.STPointN(i);
    var pLong = (point.Long).ToString().Replace(",", ".");
    var pLat = (point.Lat).ToString().Replace(",", ".");
    double dLong = double.Parse(pLong, CultureInfo.InvariantCulture);
    double dLat = double.Parse(pLat, CultureInfo.InvariantCulture);
    kmlCoordinates.Add(new Vector(dLat, dLong)); //one point od polygon
}

sqlg=SqlGeography.STPolyFromText（新的SqlChars）(
城镇。城镇边界。驰名价值。驰名文本），
城镇、城镇边界、协调体系）；
对于（int i=1；i求解它，在方法
STMPolyFromText
中，我可以使用
STNumGeometries
获得多边形数组

sqlg = SqlGeography.STMPolyFromText(
new SqlChars(town.TownBoundary.WellKnownValue.WellKnownText),
town.TownBoundary.CoordinateSystemId);
for (int i = 1; i <= sqlg.STNumGeometries(); i++)
{
 SqlGeography poly = sqlg.STGeometryN(i);
 //foreach poly
} 

sqlg=SqlGeography.STMPolyFromText(
新SqlChars（town.TownBoundary.WellKnownValue.WellKnownText），
城镇、城镇边界、协调体系）；
对于（int i=1；i