asp.Net + google map根据坐标点计算行动里程数

/// <summary> /// 地球半径 /// </summary> private const double EARTH_RADIUS = 6378.137; /// <summary> /// 计算两点间的距离，传入两点的经度和纬度 /// </summary> /// <param name="lat1"></param> /// <param name="lng1"></param> ///<param name="lat2"></param> /// <param name="lng2"></param> /// <returns></returns> public static double GetDistance(double lat1, double lng1, double lat2, double lng2) { double radLat1 = rad(lat1); double radLat2 = rad(lat2); double a = radLat1 - radLat2; double b = rad(lng1) - rad(lng2); double s = 2 * Math.Asin(Math.Sqrt(Math.Pow(Math.Sin(a / 2), 2) + Math.Cos(radLat1) * Math.Cos(radLat2) * Math.Pow(Math.Sin(b / 2), 2))); s = s * EARTH_RADIUS; s = Math.Round(s * 10000) / 10000; return s; } private static double rad(double d) { return d * Math.PI / 180.0; }