地图坐标转换

核心代码

 /// <summary>
 /// 地图坐标转换
 /// </summary>
 public class Map
 {

     /****************************************************/
     #region 坐标转换

     private const double pi = 3.14159265358979324;
     private const double x_pi = 3.14159265358979324 * 3000.0 / 180.0;

     //克拉索天斯基椭球体参数值
     private const double a = 6378245.0;
     //第一偏心率
     private const double ee = 0.00669342162296594323;

     //中国大陆，高德和谷歌用的都是GCJ-02

     /// <summary>
     /// GCJ-02转换BD-09  高德转百度
     /// </summary>
     /// <param name="gd_lon"></param>
     /// <param name="gd_lat"></param>
     /// <returns></returns>
     public double[] GCJ02_to_BD09(double gd_lon, double gd_lat)
     {
         double[] BD09_lon_lat = new double[2];
         double x = gd_lon, y = gd_lat;
         double z = Math.Sqrt(x * x + y * y) + 0.00002 * Math.Sin(y * x_pi);
         double theta = Math.Atan2(y, x) + 0.000003 * Math.Cos(x * x_pi);
         double bd_lon = z * Math.Cos(theta) + 0.0065;
         double bd_lat = z * Math.Sin(theta) + 0.006;
         BD09_lon_lat[0] = bd_lon;
         BD09_lon_lat[1] = bd_lat;
         return BD09_lon_lat;
     }

     /// <summary>
     /// BD-09转换GCJ-02  百度转高德
     /// </summary>
     /// <param name="bd_lon"></param>
     /// <param name="bd_lat"></param>
     /// <returns></returns>
     public double[] BD09_to_GCJ02(double bd_lon, double bd_lat)
     {
         double[] GCJ02_lon_lat = new double[2];
         double x = bd_lon - 0.0065, y = bd_lat - 0.006;
         double z = Math.Sqrt(x * x + y * y) - 0.00002 * Math.Sin(y * x_pi);
         double theta = Math.Atan2(y, x) - 0.000003 * Math.Cos(x * x_pi);
         double gd_lon = z * Math.Cos(theta);
         double gd_lat = z * Math.Sin(theta);
         GCJ02_lon_lat[0] = gd_lon;
         GCJ02_lon_lat[1] = gd_lat;
         return GCJ02_lon_lat;
     }


     /// <summary>
     /// WGS-84转换GCJ-02 GPS转高德
     /// </summary>
     /// <param name="wg_lon"></param>
     /// <param name="wg_lat"></param>
     /// <returns></returns>
     public double[] WGS84_to_GCJ02(double wg_lon, double wg_lat)
     {
         double[] GCJ02_lon_lat = new double[2];
         if (OutOfChina(wg_lon, wg_lat))
         {
             GCJ02_lon_lat[0] = wg_lon;
             GCJ02_lon_lat[1] = wg_lat;
             return GCJ02_lon_lat;
         }
         double dLon = TransformLon(wg_lon - 105.0, wg_lat - 35.0);
         double dLat = TransformLat(wg_lon - 105.0, wg_lat - 35.0);
         double radLat = wg_lat / 180.0 * pi;
         double magic = Math.Sin(radLat);
         magic = 1 - ee * magic * magic;
         double sqrtMagic = Math.Sqrt(magic);
         dLon = (dLon * 180.0) / (a / sqrtMagic * Math.Cos(radLat) * pi);
         dLat = (dLat * 180.0) / ((a * (1 - ee)) / (magic * sqrtMagic) * pi);
         double lng = wg_lon + dLon;
         double lat = wg_lat + dLat;
         GCJ02_lon_lat[0] = lng;
         GCJ02_lon_lat[1] = lat;
         return GCJ02_lon_lat;
     }

     /// <summary>
     /// GCJ-02转换WGS-84 高德转GPS
     /// </summary>
     /// <param name="gd_lon"></param>
     /// <param name="gd_lat"></param>
     /// <returns></returns>
     public static double[] GCJ02_to_WGS84(double gd_lon, double gd_lat)
     {
         double[] WGS84_lon_lat = new double[2];

         double dLon = TransformLon(gd_lon - 105.0, gd_lat - 35.0);
         double dLat = TransformLat(gd_lon - 105.0, gd_lat - 35.0);
         double radLat = gd_lat / 180.0 * pi;
         double magic = Math.Sin(radLat);
         magic = 1 - ee * magic * magic;
         double sqrtMagic = Math.Sqrt(magic);
         dLon = (dLon * 180.0) / (a / sqrtMagic * Math.Cos(radLat) * pi);
         dLat = (dLat * 180.0) / ((a * (1 - ee)) / (magic * sqrtMagic) * pi);
         double lng = gd_lon - dLon;
         double lat = gd_lat - dLat;
         WGS84_lon_lat[0] = lng;
         WGS84_lon_lat[1] = lat;
         return WGS84_lon_lat;
     }

     public void Transform(double wg_lon, double wg_lat, double[] lng_lat)
     {
         if (OutOfChina(wg_lon, wg_lat))
         {
             lng_lat[0] = wg_lon;
             lng_lat[1] = wg_lat;
             return;
         }
         double dLon = TransformLon(wg_lon - 105.0, wg_lat - 35.0);
         double dLat = TransformLat(wg_lon - 105.0, wg_lat - 35.0);

         double radLat = wg_lat / 180.0 * pi;
         double magic = Math.Sin(radLat);
         magic = 1 - ee * magic * magic;
         double sqrtMagic = Math.Sqrt(magic);
         dLon = (dLon * 180.0) / (a / sqrtMagic * Math.Cos(radLat) * pi);
         dLat = (dLat * 180.0) / ((a * (1 - ee)) / (magic * sqrtMagic) * pi);

         lng_lat[0] = wg_lon + dLon;
         lng_lat[1] = wg_lat + dLat;

     }

     /// <summary>
     /// 判断是否在中国区域外
     /// </summary>
     /// <param name="lon"></param>
     /// <param name="lat"></param>
     /// <returns></returns>
     private bool OutOfChina(double lon, double lat)
     {
         if (lon < 72.004 || lon > 137.8347)
             return true;
         if (lat < 0.8293 || lat > 55.8271)
             return true;
         return false;
     }

     /// <summary>
     /// 经度加密公式
     /// </summary>
     /// <param name="x"></param>
     /// <param name="y"></param>
     /// <returns></returns>
     private static double TransformLon(double x, double y)
     {
         double ret = 300.0 + x + 2.0 * y + 0.1 * x * x + 0.1 * x * y + 0.1 * Math.Sqrt(Math.Abs(x));
         ret += (20.0 * Math.Sin(6.0 * x * pi) + 20.0 * Math.Sin(2.0 * x * pi)) * 2.0 / 3.0;
         ret += (20.0 * Math.Sin(x * pi) + 40.0 * Math.Sin(x / 3.0 * pi)) * 2.0 / 3.0;
         ret += (150.0 * Math.Sin(x / 12.0 * pi) + 300.0 * Math.Sin(x / 30.0 * pi)) * 2.0 / 3.0;
         return ret;
     }

     /// <summary>
     /// 纬度加密公式
     /// </summary>
     /// <param name="x"></param>
     /// <param name="y"></param>
     /// <returns></returns>
     private static double TransformLat(double x, double y)
     {
         double ret = -100.0 + 2.0 * x + 3.0 * y + 0.2 * y * y + 0.1 * x * y + 0.2 * Math.Sqrt(Math.Abs(x));
         ret += (20.0 * Math.Sin(6.0 * x * pi) + 20.0 * Math.Sin(2.0 * x * pi)) * 2.0 / 3.0;
         ret += (20.0 * Math.Sin(y * pi) + 40.0 * Math.Sin(y / 3.0 * pi)) * 2.0 / 3.0;
         ret += (160.0 * Math.Sin(y / 12.0 * pi) + 320 * Math.Sin(y * pi / 30.0)) * 2.0 / 3.0;
         return ret;
     }

     #endregion
     /****************************************************/

 }