最近在研究Kml怎么转化为Shape文件，因为客户中很多在原来采集了一部分数据都是在google Earth中，而我们的应用中特别需要这份数据，所以打算先在GE中把这份数据导出为Kml或Kmz文件，然后我们的应用系统把Kml或Kmz数据转化为Shape，再导入到系统中。
这样做优点是：导出的Shape数据能够在很多GIS平台中读取，缺点是，会丢失Kml或Kmz的符号等信息；
我们第一阶段的目标是：只解析Kml中的点、线、面，对于贴地图片什么的暂时不考虑；
在以上的目的上我们选择了GDAL作为GIS的平台，之所以选择他是因为他不需要安装直接部署就能使用（绿色），查找一些资料发现OGR可以解析Kml数据，但是我却没有找到相关的资料方法，所以索性，自己解析Kml，要解析Kml看了好些Kml的编码资料，大概找出了编码规则开始着手解析；废话少说，直接补充解析的代码：
1.KMLPlacemarker接口，包含了Kml中Placemarker下的信息
/// <summary>
/// IKMLPlacemarker
/// </summary>
public interface IKMLPlacemarker
{
#region 成员属性
/// <summary>
/// 名称
/// </summary>
string Name { set; get; }
/// <summary>
/// 描述信息
string Description { set; get; }
/// <summary>
/// 样式路径
/// </summary>
string StyleURL { set; get; }
/// <summary>
/// 图形类型
/// </summary>
enumKmlGeometryType GeometryType { set; get; }
/// <summary>
/// KMLGeometry
/// </summary>
IKMLGeometry Geometry { set; get; }
#endregion
#region 成员方法
/// <summary>
/// 初始化
/// </summary>
/// <param name="placemarkerNode">PlacemarkerNode</param>
/// <returns>是否成功</returns>
bool Initial(System.Xml.XmlNode placemarkerNode) ;
#endregion
}
2.KMLGeometry空接口，作为KMLPlacemarker的一个属性
/// <summary>
/// KMLGeometry
/// </summary>
public interface IKMLGeometry
{
}
3.KMLPoint接口 KML中点
/// <summary>
/// IKMLPoint
/// </summary>
public interface IKMLPoint
{
#region 成员属性
/// <summary>
/// 坐标信息
/// </summary>
string Coordinates { set; get; }
#endregion
#region 成员方法
/// <summary>
/// 初始化
/// </summary>
/// <param name="pointXmlNode">point节点</param>
/// <returns>是否成功</returns>
bool InitialPoint(System.Xml.XmlNode pointXmlNode);
#endregion
}
4. KMLPolyline接口 KML中线类型
/// <summary>
/// IKMLPolyLine
/// </summary>
public interface IKMLPolyline
{
#region 成员属性
/// <summary>
/// 坐标信息
/// </summary>
string Coordinates { set; get; }
#endregion
#region 成员方法
/// <summary>
/// 初始化
/// </summary>
/// <param name="polylineXmlNode">polyLine节点</param>
/// <returns>是否成功</returns>
bool InitialPolyline(System.Xml.XmlNode polylineXmlNode);
#endregion
}
5.KMLPolygon接口 Kml中的面类型（不是多面，是面）
/// <summary>
/// IKMLPolygon
/// </summary>
public interface IKMLPolygon
{
#region 成员属性
/// <summary>
/// 坐标信息-内轮廓
/// </summary>
string Coordinates_InnerBoundary { set; get; }
/// <summary>
/// 坐标信息-外轮廓
/// </summary>
string Coordinates_OuterBoundary { set; get; }
#endregion
#region 成员方法
/// <summary>
/// 初始化
/// </summary>
/// <param name="polygonXmlNode">polyLine节点</param>
/// <returns>是否成功</returns>
bool InitialPolygon(System.Xml.XmlNode polygonXmlNode);
#endregion
}
6. KMLPoint的实现
/// <summary>
/// KMLPoint
/// </summary>
public class KMLPoint : IKMLPoint, IKMLGeometry
{
#region IKMLPoint 成员
#region 成员属性
/// <summary>
/// 坐标信息
/// </summary>
public string Coordinates { set; get; }
#endregion
#region 成员方法
/// <summary>
/// 初始化
/// </summary>
/// <param name="pointXmlNode">point节点</param>
/// <returns>是否成功</returns>
public bool InitialPoint(System.Xml.XmlNode pointXmlNode)
{
System.Xml.XmlNode childNode = null;
for (int k = 0; k < pointXmlNode.ChildNodes.Count; k++)
{
childNode = pointXmlNode.ChildNodes[k];
switch (childNode.Name)
{
case "coordinates":
{
this.Coordinates = childNode.InnerText;
break;
}
default:
{
break;
}
}
}
return true;
}
#endregion
#endregion
}
7.KMLPolyline的实现
/// <summary>
/// KMLPolyline
/// </summary>
public class KMLPolyline : IKMLPolyline, IKMLGeometry
{
#region IKMLPolyline 成员
#region 成员属性
/// <summary>
/// 坐标信息
/// </summary>
public string Coordinates { set; get; }
#endregion
#region 成员方法
/// <summary>
/// 初始化
/// </summary>
/// <param name="polylineXmlNode">polyLine节点</param>
/// <returns>是否成功</returns>
public bool InitialPolyline(System.Xml.XmlNode polylineXmlNode)
{
System.Xml.XmlNode childNode = null;
for (int k = 0; k < polylineXmlNode.ChildNodes.Count; k++)
{
childNode = polylineXmlNode.ChildNodes[k];
switch (childNode.Name)
{
case "coordinates":
{
this.Coordinates = childNode.InnerText;
break;
}
default:
{
break;
}
}
}
return true;
}
#endregion
#endregion
}
8. KMLPolygon的实现
/// <summary>
/// KMLPolygon
/// </summary>
public class KMLPolygon : IKMLPolygon, IKMLGeometry
{
#region IKMLPolygon 成员
#region 成员属性
/// <summary>
/// 坐标信息-内轮廓
/// </summary>
public string Coordinates_InnerBoundary { set; get; }
/// <summary>
/// 坐标信息-外轮廓
/// </summary>
public string Coordinates_OuterBoundary { set; get; }
#endregion
#region 成员方法
/// <summary>
/// 初始化
/// </summary>
/// <param name="polygonXmlNode">polyLine节点</param>
/// <returns>是否成功</returns>
public bool InitialPolygon(System.Xml.XmlNode polygonXmlNode)
{
System.Xml.XmlNode childNode = null;
for (int i = 0; i < polygonXmlNode.ChildNodes.Count; i++)
{
childNode = polygonXmlNode.ChildNodes[i];
switch (childNode.Name)
{
case "outerBoundaryIs":
{
this.Coordinates_OuterBoundary = GetCoordinates(childNode);
break;
}
case "innerBoundaryIs":
{
this.Coordinates_InnerBoundary = GetCoordinates(childNode);
break;
}
default:
{
break;
}
}
}
return true;
}
#endregion
#endregion
#region 私有方法
/// <summary>
/// 获得轮廓线坐标集
/// </summary>
/// <param name="boundaryNode">轮廓线节点</param>
/// <returns>坐标集</returns>
private string GetCoordinates(System.Xml.XmlNode boundaryNode)
{
System.Xml.XmlNode childNodeBoundary = null;
System.Xml.XmlNode childNodeLinering = null;
for (int k = 0; k < boundaryNode.ChildNodes.Count; k++)
{
childNodeBoundary = boundaryNode.ChildNodes[k];
if(childNodeBoundary.Name!="LinearRing") continue;
for (int j = 0; j < childNodeBoundary.ChildNodes.Count; j++)
{
childNodeLinering= childNodeBoundary.ChildNodes[j];
switch (childNodeLinering.Name)
{
case "coordinates":
{
return childNodeLinering.InnerText;
}
default:
{
break;
}
}
}
}
return string.Empty; ;
}
#endregion
}
9.KmlGeometryType枚举类型
/// <summary>
/// KmlGeometry类型枚举
/// </summary>
public enum enumKmlGeometryType
{
/// <summary>
/// 未知
/// </summary>
KMLNull=0,
/// <summary>
/// 点
/// </summary>
KMLPoint=1,
/// <summary>
/// 线
/// </summary>
KMLPolyline=2,
/// <summary>
/// 面
/// </summary>
KMLPolygon=3
}
10.KMLPlacemarker的实现
/// <summary>
/// KMLPlacemarker
/// </summary>
public class KMLPlacemarker:IKMLPlacemarker
{
#region IKMLPlacemarker 成员
#region 成员属性
/// <summary>
/// 名称
/// </summary>
public string Name { set; get; }
/// <summary>
/// 描述信息
public string Description { set; get; }
/// <summary>
/// 样式路径
/// </summary>
public string StyleURL { set; get; }
/// <summary>
/// 图形类型
/// </summary>
public enumKmlGeometryType GeometryType { set; get; }
/// <summary>
/// KMLGeometry
/// </summary>
public IKMLGeometry Geometry { set; get; }
#endregion
#region 成员方法
/// <summary>
/// 初始化
/// </summary>
/// <param name="placemarkerNode">PlacemarkerNode</param>
/// <returns>是否成功</returns>
public bool Initial(System.Xml.XmlNode placemarkerNode)
{
if (placemarkerNode == null) return false;
if (placemarkerNode.ChildNodes.Count < 1) return false;
System.Xml.XmlNode childNode = null;
for (int i = 0; i < placemarkerNode.ChildNodes.Count; i++)
{
childNode = placemarkerNode.ChildNodes[i];
switch (childNode.Name)
{
case "name":
{
this.Name = childNode.InnerText;
break;
}
case "description":
{
this.Description = childNode.InnerText;
break;
}
case "styleUrl":
{
this.StyleURL = childNode.InnerText;
break;
}
case "Point":
{
this.GeometryType = enumKmlGeometryType.KMLPoint;
this.Geometry = new KMLPoint();
(this.Geometry as IKMLPoint).InitialPoint(childNode);
break;
}
case "LineString":
{
this.GeometryType = enumKmlGeometryType.KMLPolyline;
this.Geometry = new KMLPolyline();
(this.Geometry as IKMLPolyline).InitialPolyline(childNode);
break;
}
case "Polygon":
{
this.GeometryType = enumKmlGeometryType.KMLPolygon;
this.Geometry = new KMLPolygon();
(this.Geometry as IKMLPolygon).InitialPolygon(childNode);
break;
}
default:
break;
}
}
return true;
}
#endregion
#endregion
}
11.1KML解析为KMLPlacemarker的方法：（后续会补充上，这只是一部分）
/// <summary>
/// 转换KML为Shape文件
/// </summary>
/// <param name="kmlFilePath">kml文件路径</param>
/// <param name="shapeDirectoryPath">shape文件夹路径</param>
/// <returns></returns>
public bool ConvertKMLToShape(string kmlFilePath, string shapeDirectoryPath)
{
// 判断
if (string.IsNullOrEmpty(kmlFilePath)) return false;
if (string.IsNullOrEmpty(shapeDirectoryPath)) return false;
if (!System.IO.File.Exists(kmlFilePath)) return false;
if (!System.IO.Directory.Exists(shapeDirectoryPath)) { System.IO.Directory.CreateDirectory(shapeDirectoryPath); };
string kmlFileName = System.IO.Path.GetFileNameWithoutExtension(kmlFilePath);
System.Xml.XmlDocument xmlDocument = new System.Xml.XmlDocument();
xmlDocument.Load(kmlFilePath);
System.Xml.XmlNodeList placeMarkerNodeList = xmlDocument.GetElementsByTagName("Placemark");
System.Xml.XmlNode placeMarkerNode = null;
IList<IKMLPlacemarker> kmlPlaceMarkers_Point = new List<IKMLPlacemarker>(); ;
IList<IKMLPlacemarker> kmlPlaceMarkers_Polyline = new List<IKMLPlacemarker>(); ;
IList<IKMLPlacemarker> kmlPlaceMarkers_Polygon = new List<IKMLPlacemarker>(); ;
IKMLPlacemarker kmlPlacemarker = null;
string coordinates = string.Empty;
int i = 0;
for (i = 0; i < placeMarkerNodeList.Count; i++)
{
placeMarkerNode = placeMarkerNodeList.Item(i);
kmlPlacemarker = new KMLPlacemarker();
kmlPlacemarker.Initial(placeMarkerNode);
switch (kmlPlacemarker.GeometryType)
{
case enumKmlGeometryType.KMLPoint:
kmlPlaceMarkers_Point.Add(kmlPlacemarker);
break;
case enumKmlGeometryType.KMLPolyline:
kmlPlaceMarkers_Polyline.Add(kmlPlacemarker);
break;
case enumKmlGeometryType.KMLPolygon:
kmlPlaceMarkers_Polygon.Add(kmlPlacemarker);
break;
default:
break;
}
}
////////////////////////////////////////隐掉了部分生成Shape的代码/////////////////////////////////////////
return true;
}
这时候就能把Kml文件解析为自己定义的KmlPlacemarker，它包含了Kml中Placemarker中的所有信息；