DotSpatial 创建面状要素——含空洞

private void toolStripButton23_Click(object sender, EventArgs e)
{
//选择图层
FeatureSet fs = null;
fs = (FeatureSet) map1.Layers[0].DataSet;

//面层增加要素

//定义坐标List
List<Coordinate> polygonArray1 = new List<Coordinate>();
polygonArray1.Add(new Coordinate(625105, 5050458));
polygonArray1.Add(new Coordinate(627115, 5050486));
polygonArray1.Add(new Coordinate(627103, 5048421));
polygonArray1.Add(new Coordinate(625021, 5048466));
polygonArray1.Add(new Coordinate(625105, 5050458));
//创建外环
var outerRing = new LinearRing(polygonArray1);

//判断坐标数组是否为顺时针，否则数组反转
if (CgAlgorithms.IsCounterClockwise(outerRing.Coordinates))
{
outerRing = new LinearRing(outerRing.Reverse());
}
//定义内环1——空洞1
var hole1 = new LinearRing(new List<Coordinate>()
{
new Coordinate(626304, 5050188),
new Coordinate(626721, 5050188),
new Coordinate(626715, 5049777),
new Coordinate(626394, 5049625),
new Coordinate(626186, 5049743),
new Coordinate(626208, 5050014),
new Coordinate(626304, 5050188),
});
//是否为逆时针，否则反转，必须是逆时针的，否则创建的要素的图形异常
if (!CgAlgorithms.IsCounterClockwise(hole1.Coordinates))
{
hole1 = new LinearRing(hole1.Reverse());
}
//定义内环2
var hole2 = new LinearRing(new List<Coordinate>()
{
new Coordinate(625454, 5050228),
new Coordinate(625876, 5050250),
new Coordinate(625876, 5049710),
new Coordinate(625426, 5049743),
new Coordinate(625454, 5050228)
});
//是否为逆时针，否则反转，必须是逆时针的，否则创建的要素的图形异常
if (!CgAlgorithms.IsCounterClockwise(hole2.Coordinates))
{
hole2 = new LinearRing(hole2.Reverse());
}

//——将hole1、hole2 添加到数组中，进行坐标翻转
//LinearRing[] lr2 = { hole1,hole2 };

////make sure the holes are oriented counterclockwise
//for (int i = 0; i < lr2.Length; i++)
//{
// if (!CgAlgorithms.IsCounterClockwise(lr2[i].Coordinates))
// {
// lr2[i] = new LinearRing(lr2[i].Reverse());
// }
//}

//创建要素
Polygon pP = new Polygon(outerRing, new ILinearRing[] {hole1, hole2});

IFeature polygonFeature = fs.AddFeature(pP);
polygonID = polygonID + 1;
polygonFeature.DataRow["Text"] = polygonID;
fs.InitializeVertices();
fs.Save();
map1.ResetBuffer();

}