30 lines
1.0 KiB
C#
30 lines
1.0 KiB
C#
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namespace LY.App.Common
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{
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public static class GisHelper
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{
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/// <summary>
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/// 计算两点之间的距离
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/// </summary>
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/// <param name="lat1"></param>
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/// <param name="lon1"></param>
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/// <param name="lat2"></param>
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/// <param name="lon2"></param>
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/// <returns></returns>
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public static double HaversineDistance(double lat1, double lon1, double lat2, double lon2)
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{
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const double R = 6371000.0; // 地球半径（单位：米）
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double dLat = ToRadians(lat2 - lat1);
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double dLon = ToRadians(lon2 - lon1);
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double a = Math.Sin(dLat / 2) * Math.Sin(dLat / 2) +
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Math.Cos(ToRadians(lat1)) * Math.Cos(ToRadians(lat2)) *
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Math.Sin(dLon / 2) * Math.Sin(dLon / 2);
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double c = 2 * Math.Atan2(Math.Sqrt(a), Math.Sqrt(1 - a));
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return R * c;
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}
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static double ToRadians(double degrees) => degrees * Math.PI / 180.0;
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}
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}
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