各类坐标系相互之间的转换（84互转GC02，GC02互转BD09）

在遥感行业我们经常会用到各类的坐标系相互之间的转换，常见的度分秒转化为度很简单，直接上代码：

        //经纬度
        ////118度48分54.152秒=118+(48/60)+(54.152/3600)=118.81504度
        public static string GetLongLatByDMS(byte Deg, byte Mis, byte Sec)
        {
            decimal result = Convert.ToInt32(Deg) + (Convert.ToDecimal(Mis) / 60) + (Convert.ToDecimal(Sec) / 3600);

            return result.ToString();
        }

各个坐标系之间的相互转换：

定义各个变量

	public static double pi = 3.1415926535897932384626;
	public static double a = 6378245.0;
	public static double ee = 0.00669342162296594323;

	private static final double EARTH_RADIUS = 6378.137;// 地球半径

	private static double rad(double d) {
		return d * Math.PI / 180.0;
	}

转换方法代码：

/**
	 * * 火星坐标系 (GCJ-02) 与百度坐标系 (BD-09) 的转换算法 * * 将 BD-09 坐标转换成GCJ-02 坐标 * * @param
	 * bd_lat * @param bd_lon * @return
	 */
	public static Gps bd09_To_Gcj02(double bd_lat, double bd_lon) {
		double x = bd_lon - 0.0065, y = bd_lat - 0.006;
		double z = Math.sqrt(x * x + y * y) - 0.00002 * Math.sin(y * pi);
		double theta = Math.atan2(y, x) - 0.000003 * Math.cos(x * pi);
		double gg_lon = z * Math.cos(theta);
		double gg_lat = z * Math.sin(theta);
		return new Gps(gg_lat, gg_lon);
	}

	public 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;
	}

	public static Gps transform(double lat, double lon) {
		if (outOfChina(lat, lon)) {
			return new Gps(lat, lon);
		}
		double dLat = transformLat(lon - 105.0, lat - 35.0);
		double dLon = transformLon(lon - 105.0, lat - 35.0);
		double radLat = lat / 180.0 * pi;
		double magic = Math.sin(radLat);
		magic = 1 - ee * magic * magic;
		double sqrtMagic = Math.sqrt(magic);
		dLat = (dLat * 180.0) / ((a * (1 - ee)) / (magic * sqrtMagic) * pi);
		dLon = (dLon * 180.0) / (a / sqrtMagic * Math.cos(radLat) * pi);
		double mgLat = lat + dLat;
		double mgLon = lon + dLon;
		return new Gps(mgLat, mgLon);
	}

	public 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;
	}

	private static boolean outOfChina(double lat, double lon) {
		if (lon < 72.004 || lon > 137.8347)
			return true;
		if (lat < 0.8293 || lat > 55.8271)
			return true;
		return false;
	}

	/**
	 * 84 to 火星坐标系 (GCJ-02) World Geodetic System ==> Mars Geodetic System
	 *
	 * @param lat
	 * @param lon
	 * @return
	 */
	public static Gps gps84_To_Gcj02(double lat, double lon) {
		if (outOfChina(lat, lon)) {
			return null;
		}
		double dLat = transformLat(lon - 105.0, lat - 35.0);
		double dLon = transformLon(lon - 105.0, lat - 35.0);
		double radLat = lat / 180.0 * pi;
		double magic = Math.sin(radLat);
		magic = 1 - ee * magic * magic;
		double sqrtMagic = Math.sqrt(magic);
		dLat = (dLat * 180.0) / ((a * (1 - ee)) / (magic * sqrtMagic) * pi);
		dLon = (dLon * 180.0) / (a / sqrtMagic * Math.cos(radLat) * pi);
		double mgLat = lat + dLat;
		double mgLon = lon + dLon;
		return new Gps(mgLat, mgLon);
	}

	public static Gps gcj_To_Gps84(double lat, double lon) {
		Gps gps = transform(lat, lon);
		double lontitude = lon * 2 - gps.getWgLon();
		double latitude = lat * 2 - gps.getWgLat();
		return new Gps(latitude, lontitude);
	}

	static double x_pi = 3.14159265358979324 * 3000.0 / 180.0;

	// WGS84坐标系转成BD09
	public static String WGS84ToBd09(double gg_lat, double gg_lon) {

		String[] redbstring = transform(gg_lat, gg_lon).toString().split("\\,");// WGS84

		gg_lon = Double.parseDouble(redbstring[0]);
		gg_lat = Double.parseDouble(redbstring[1]);

		// GCJ-02 转 DB09
		double bd_lat;
		double bd_lon;
		double x = gg_lon, y = gg_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);
		bd_lon = z * Math.cos(theta) + 0.0065;
		bd_lat = z * Math.sin(theta) + 0.006;

		System.out.println("BD:" + bd_lat + "," + bd_lon);

		return bd_lon + "," + bd_lat;
	}

	/**
	 * (BD-09)-->84
	 *
	 * @param bd_lat
	 * @param bd_lon
	 * @return
	 */
	public static Gps bd09_To_Gps84(double bd_lat, double bd_lon) {

		Gps gcj02 = bd09_To_Gcj02(bd_lat, bd_lon);
		Gps map84 = gcj_To_Gps84(gcj02.getWgLat(), gcj02.getWgLon());
		return map84;
	}

以上！