地图按范围查找-经纬度计算

C#

private const double EARTH_RADIUS = 6378.137;//地球半径
        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;
        }

 

public static double GetShortDistance(double lon1, double lat1, double lon2, double lat2)
        {
            double DEF_PI = 3.14159265359; // PI
            double DEF_2PI = 6.28318530712; // 2*PI
            double DEF_PI180 = 0.01745329252; // PI/180.0
            double DEF_R = 6370693.5; // radius of earth
            double ew1, ns1, ew2, ns2;
            double dx, dy, dew;
            double distance;

            // 角度转换为弧度
            ew1 = lon1 * DEF_PI180;
            ns1 = lat1 * DEF_PI180;
            ew2 = lon2 * DEF_PI180;
            ns2 = lat2 * DEF_PI180;

            // 经度差
            dew = ew1 - ew2;
            // 若跨东经和西经180 度，进行调整
            if (dew > DEF_PI)
                dew = DEF_2PI - dew;
            else if (dew < -DEF_PI)
                dew = DEF_2PI + dew;
            dx = DEF_R * Math.Cos(ns1) * dew;     // 东西方向长度(在纬度圈上的投影长度)
            dy = DEF_R * (ns1 - ns2);             // 南北方向长度(在经度圈上的投影长度)

            // 勾股定理求斜边长
            distance = Math.Sqrt(dx * dx + dy * dy);
            return distance;
        }

 

SQL

select id,hotel_code,bname,image,serviceId,fjmoney,score,lon,lat,(2 * 6378.137* ASIN(SQRT(power(SIN(PI()*(28.984223-lat)/360),2)
+COS(PI()*28.984223/180)* COS(lat * PI()/180)*power(SIN(PI()*(112.92671-lon)/360),2)))) as distance 
 into #temp from hotelid   

lon 经坐标

lat 纬坐标

lat 28.984223
lon 112.92671