如何在c#中获得KML多边形和多几何值

Question

我可以读取和获取KML数据Placemark值使用这个代码

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml;
using System.Xml.Linq;
namespace ConsoleApplication1
{
    class Program
    {
        const string FILENAME = @"c:temptest.xml";
        static void Main(string[] args)
        {
            XDocument doc = XDocument.Load(FILENAME);
            List<XElement> placemarks = doc.Descendants().Where(x => x.Name.LocalName == "Placemark").ToList();
            List<string> states = placemarks.Descendants().Where(x => x.Name.LocalName == "name").Select(x => x.Value).ToList();
        }
    }
}

但我不知道如何获得KML数据，如果它有以下细节:

1. 示例:阿拉巴马州的KML格式，如

   <Polygon> <outerBoundaryIs> <LinearRing> <coordinates>-85.070067,31.980703,0.0 -85.11515,31.907425,0.0 -85.135567,31.854884,0.0 -85.0567,32.017377,0.0 -85.070067,31.980703,0.0</coordinates> </LinearRing> </outerBoundaryIs> </Polygon>

2. 示例:德克萨斯州的KML格式如

   <MultiGeometry> <Polygon> <outerBoundaryIs> <LinearRing> <coordinates>-161.333785,58.703653</coordinates> </LinearRing> </outerBoundaryIs> </Polygon> <Polygon> <outerBoundaryIs> <LinearRing> <coordinates>-131.594177,55.106316,55.23548,0.0</coordinates> </LinearRing> </outerBoundaryIs> </Polygon> </MultiGeometry>

我尝试了这个LINQ过程来获得多边形值:

List<string> states = placemarks.Descendants().Where(x => x.Name.LocalName == "Polygon").Select(x => x.Value).ToList();

输出:

-85.070067,31.980703,0.0 -85.11515,31.907425,0.0 -85.135567,31.854884,0.0 -85.0567,32.017377,0.0 -85.070067,31.980703,0.0

在我尝试用下面的格式替换坐标并复制/粘贴到融合表位置预览后，地图的工作完全符合预期。

<Polygon> <outerBoundaryIs> <LinearRing> <coordinates>-85.070067,31.980703,0.0 -85.11515,31.907425,0.0 -85.135567,31.854884,0.0 -85.0567,32.017377,0.0 -85.070067,31.980703,0.0</coordinates> </LinearRing> </outerBoundaryIs> </Polygon>

但是当我尝试使用相同的方式获得Multigeometry值时:

List<string> states = placemarks.Descendants().Where(x => x.Name.LocalName == "MultiGeometry").Select(x => x.Value).ToList();

我得到了这样的输出:

-161.333785, 58.703653 - -131.594177, 55.106316, 55.23548, 0.0

但我不知道如何获得详细信息

Answer 1

"我试着用下面的格式替换坐标，并将它们复制/粘贴到融合表位置预览中，地图的效果完全符合预期。"

<Polygon> <outerBoundaryIs> <LinearRing> <coordinates>-85.070067,31.980703,0.0 -85.11515,31.907425,0.0 -85.135567,31.854884,0.0 -85.0567,32.017377,0.0 -85.070067,31.980703,0.0</coordinates> </LinearRing> </outerBoundaryIs> </Polygon>

如果您想要XElement的XML标记，只需调用ToString()而不是获取Value属性:

List<string> states = placemarks.Descendants()
                                .Where(x => x.Name.LocalName == "MultiGeometry")
                                .Select(x => x.ToString())
                                .ToList();

. .或者如果你真的想从MultiGeometry:

获得单独的坐标值

List<string> states = placemarks.Descendants()
                                .Where(x => x.Name.LocalName == "MultiGeometry")
                                .Descendants()
                                .Where(x => x.Name.LocalName == "Polygon")
                                .Select(x => x.Value)
                                .ToList();