/// <summary>
/// 对几何面从web墨卡托投影转换为适用于高德、腾讯的经纬度坐标（GCJ-02)
/// </summary>
/// <param name="wkt"></param>
/// <returns></returns>
public static string Polygon_3857toGCJ02(String wkt)
{
Geometry polygon = Geometry.CreateFromWkt(wkt);
SpatialReference spa_3857 = new SpatialReference(wkt_3857);
SpatialReference spa_4326 = new SpatialReference(wkt_4326);
polygon.AssignSpatialReference(spa_3857);
polygon.TransformTo(spa_4326);
string[] polygon_str = { };
String polygon_json = polygon.ExportToJson(polygon_str);
JObject result_json = JObject.Parse(polygon_json) as JObject;
JArray result_polygon = result_json["coordinates"] as JArray;
Geometry gcj02_polygon = new Geometry(wkbGeometryType.wkbPolygon);
for (int i = 0; i < result_polygon.Count; i++)
{
JArray result_lines = result_polygon[i] as JArray;
Geometry gcj02_line = new Geometry(wkbGeometryType.wkbLinearRing);
for (int j = 0; j < result_lines.Count; j++)
{
JArray p = result_lines[j] as JArray;
double wgs84_lng = System.Convert.ToDouble(p[0]);
double wgs84_lat = System.Convert.ToDouble(p[1]);
double[] gcj02_coord = Coordtransform.Wgs84togcj02(wgs84_lng, wgs84_lat);
double gcj02_lng = gcj02_coord[0];
double gcj02_lat = gcj02_coord[1];
gcj02_line.AddPoint_2D(gcj02_lng, gcj02_lat);
}
gcj02_polygon.AddGeometry(gcj02_line);
}
string[] gcj02_param = { };
string gcj02__geojson = gcj02_polygon.ExportToJson(gcj02_param);
return(gcj02__geojson);
}
/// <summary>
/// 对几何线从web墨卡托投影转换为适用于高德、腾讯的经纬度坐标（GCJ-02)
/// </summary>
/// <param name="wkt"></param>
/// <returns></returns>
public static string Polyline_3857toGCJ02(String wkt)
{
Geometry polyline = Geometry.CreateFromWkt(wkt);
//定义数据源坐标系统
SpatialReference spa_3857 = new SpatialReference(wkt_3857);
//定义目标坐标系统
SpatialReference spa_4326 = new SpatialReference(wkt_4326);
polyline.AssignSpatialReference(spa_3857);
//将几何线从3857转为4326坐标
polyline.TransformTo(spa_4326);
string[] polyline_str = { };
//将几何线转为geojson字符串格式；
String polyline_json = polyline.ExportToJson(polyline_str);
//将字符串解析为json对象
JObject result_json = JObject.Parse(polyline_json) as JObject;
JArray result_polyline = result_json["coordinates"] as JArray;
Geometry gcj02_multiline = new Geometry(wkbGeometryType.wkbMultiLineString);
for (int i = 0; i < result_polyline.Count; i++)
{
JArray result_lines = result_polyline[i] as JArray;
Geometry gcj02_line = new Geometry(wkbGeometryType.wkbLineString);
for (int j = 0; j < result_lines.Count; j++)
{
JArray p = result_lines[j] as JArray;
double wgs84_lng = System.Convert.ToDouble(p[0]);
double wgs84_lat = System.Convert.ToDouble(p[1]);
//将wgs84经纬度坐标转为gcj-02经纬度坐标
double[] gcj02_coord = Coordtransform.Wgs84togcj02(wgs84_lng, wgs84_lat);
double gcj02_lng = gcj02_coord[0];
double gcj02_lat = gcj02_coord[1];
//将点连接成线
gcj02_line.AddPoint_2D(gcj02_lng, gcj02_lat);
}
//将线连接成多线
gcj02_multiline.AddGeometry(gcj02_line);
}
string[] gcj02_param = { };
//将多线转为geojson字符串格式
string gcj02__geojson = gcj02_multiline.ExportToJson(gcj02_param);
return(gcj02__geojson);
}
