參數是經緯度，C#版： 千米PRivate const double EARTH_RADIUS = 6378.137;//地球半徑private static double rad(double d){ return d * Math.PI / 180.0;} 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;}java2版：（千米)//private static double EARTH_RADIUS = 6378137.0;(米)private static double EARTH_RADIUS = 6378.137; private static double rad(double d) { return d * Math.PI / 180.0; } /** * 根據兩個位置的經緯度，來計算兩地的距離（單位為KM） * 參數為String類型 * @param lat1 用戶經度 * @param lng1 用戶緯度 * @param lat2 商家經度 * @param lng2 商家緯度 * @return */ public static String getDistance(String lat1Str, String lng1Str, String lat2Str, String lng2Str) { Double lat1 = Double.parseDouble(lat1Str); Double lng1 = Double.parseDouble(lng1Str); Double lat2 = Double.parseDouble(lat2Str); Double lng2 = Double.parseDouble(lng2Str); double radLat1 = rad(lat1); double radLat2 = rad(lat2); double difference = radLat1 - radLat2; double mdifference = rad(lng1) - rad(lng2); double distance = 2 * Math.asin(Math.sqrt(Math.pow(Math.sin(difference / 2), 2) + Math.cos(radLat1) * Math.cos(radLat2) * Math.pow(Math.sin(mdifference / 2), 2))); distance = distance * EARTH_RADIUS; distance = Math.round(distance * 10000) / 10000; String distanceStr = distance+""; distanceStr = distanceStr.substring(0, distanceStr.indexOf(".")); return distanceStr; }新聞熱點
疑難解答
