C# 获取两经纬度之间的距离
//地球半径,单位米
private const double EARTH_RADIUS = 6378137;
/// <summary>
/// 计算两点位置的距离,返回两点的距离,单位:米
/// 该公式为GOOGLE提供,误差小于0.2米
/// </summary>
/// <param name="lng1">第一点经度</param>
/// <param name="lat1">第一点纬度</param>
/// <param name="lng2">第二点经度</param>
/// <param name="lat2">第二点纬度</param>
/// <returns></returns>
public static double GetDistance(double lng1, double lat1, double lng2, double lat2)
{
double radLat1 = Rad(lat1);
double radLng1 = Rad(lng1);
double radLat2 = Rad(lat2);
double radLng2 = Rad(lng2);
double a = radLat1 - radLat2;
double b = radLng1 - radLng2;
double result = 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))) * EARTH_RADIUS;
return result;
}
/// <summary>
/// 经纬度转化成弧度
/// </summary>
/// <param name="d"></param>
/// <returns></returns>
private static double Rad(double d)
{
return (double)d * Math.PI / 180d;
}
![](https://img-blog.csdnimg.cn/30529d3cc23e49c5bbc1498435b89839.png)