非本人原创.
同事在网上找的合并速度较快
/// <summary> /// 计算合并面积(去掉岛) /// </summary> /// <param name="pArrayPolygon">图形集合</param> /// <param name="isShowError"></param> /// <returns></returns> public static IPolygon UnionOrRemoveRingFromPolygon(ArrayList pArrayPolygon, bool isShowError) {
IPolygon pPolygon_Each = null;
IPolygon pPolygon_Result = null;
IGeometryCollection pGeometryCollection = null;
ISegmentCollection pSegmentCollection_Ring = null;
object oMissing = Type.Missing;
try {
if (pArrayPolygon == null)
return null;
if (pArrayPolygon.Count == 0)
return null;
pGeometryCollection = new PolygonClass();
pPolygon_Result = pGeometryCollection as IPolygon;
for (int i = 0; i < pArrayPolygon.Count; i++) {
pPolygon_Each = pArrayPolygon[i] as IPolygon;
IGeometryCollection pGeometryCollection_Temp = null;
pGeometryCollection_Temp = pPolygon_Each as IGeometryCollection;
for (int j = 0; j < pGeometryCollection_Temp.GeometryCount; j++) {
pSegmentCollection_Ring = new RingClass();
pSegmentCollection_Ring.AddSegmentCollection(pGeometryCollection_Temp.get_Geometry(j) as ISegmentCollection);
pGeometryCollection.AddGeometry(pSegmentCollection_Ring as IGeometry, ref oMissing, ref oMissing);
}
} pPolygon_Result.SimplifyPreserveFromTo(); return pPolygon_Result;
}
catch (Exception ex) {
//if (isShowError)
// MessageBox.Show("合并(去岛)多边形发生错误,错误信息为:->\r\n" + ex.Message,
// "错误信息", MessageBoxButtons.OK, MessageBoxIcon.Error);
return null;
}
}
转载于:https://www.cnblogs.com/ITGIS/articles/1747446.html