利用Ogr将Kml转为Shape【1】

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；