2种方法都是在网上搜索来的,一种原来是java写的,一种是.net写的,java的那个我翻译成.net的了. 1:原JAVA double distanceByLnglat(double _Longitude1,   double _Latidute1,   double _Longitude2,   double _Latidute2)  {      double radLat1 = _Latidute1 * Math.PI / 180;   double radLat2 = _Latidute2 * Math.PI / 180;   double a = radLat1 - radLat2;   double b = _Longitude1 * Math.PI / 180 - _Longitude2 * Math.PI / 180;   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 * 6378137.0;// 取WGS84标准参考椭球中的地球长半径(单位:m)   s = Math.Round(s * 10000) / 10000;    return s;  }      2:原.Net public struct EarthPoint  {   public const double Ea = 6378137; // 赤道半径 WGS84标准参考椭球中的地球长半径(单位:m)     public const double Eb = 6356725; // 极半径      public readonly double Longitude,Latidute;   public readonly double Jd;   public readonly double Wd;   public readonly double Ec;   public readonly double Ed;   public EarthPoint(double _Longitude,double _Latidute)   {    Longitude = _Longitude;    Latidute = _Latidute;    Jd = Longitude * Math.PI / 180; //转换成角度    Wd = Latidute * Math.PI /180; //转换成角度    Ec = Eb + (Ea - Eb) * (90 - Latidute) / 90;    Ed = Ec * Math.Cos(Wd);   }   public double Distance(EarthPoint _Point)   {    double dx = (_Point.Jd - Jd) * Ed;    double dy = (_Point.Wd - Wd) * Ec;    return Math.Sqrt(dx * dx + dy *dy);   }  }   public static Double GetDistance(double _Longitude1,   double _Latidute1,   double _Longitude2,   double _Latidute2)  {   EarthPoint p1 = new EarthPoint(_Longitude1,_Latidute1);   EarthPoint p2 = new EarthPoint(_Longitude2,_Latidute2);   return p1.Distance(p2);     }   测试代码: DateTime   dt1=DateTime.Now;    DateTime dt2 = DateTime.Now;   TimeSpan ts1;      dt1 = DateTime.Now;   for(int i=0;i<sumCount;i++)    ss = distanceByLnglat(jd1,wd1,jd2,wd2);   dt2 = DateTime.Now;   ts1 = dt2- dt1;   this.label4.Text =  String.Format("Java:{0:N3}米 计算次数: {1:N:0} 用时: {2:N1} 毫妙",ss,sumCount,ts1.TotalMilliseconds);       dt1=DateTime.Now;    for(int i=0;i<sumCount;i++)    ss = GetDistance(jd1,wd1,jd2,wd2);   dt2 = DateTime.Now;   ts1 = dt2- dt1;   this.label3.Text =  String.Format("Net:{0:N3}米 计算次数: {1:N:0} 用时: {2:N1} 毫妙",ss,sumCount,ts1.TotalMilliseconds);     第一种方法用时基本上是第二种方法的用时的2倍! 此处没有比较2种语言的意思,因为根本没有在2种环境下运行,这里只比较了算法的执行效率而已!

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