C#经纬度加减运算(度°分′秒″格式)

经度是分和秒是按60进位，如果要做运算第一步就是转换成浮点数，之后就是计算和还原。

using System.Text.RegularExpressions;



public static double DegreeFromString(string str)

{

    Match match = Regex.Match(str, 

        @"(?<hour>[0-9]+)°(?<minute>[0-9]+)(′|')(?<second>[0-9]+(.[0-9]+)?)(″|""|'')");

    if (match.Success)

    {

        double hour = 0, minute = 0, second = 0;

        double.TryParse(match.Result("${hour}"), out hour);

        double.TryParse(match.Result("${minute}"), out minute);

        double.TryParse(match.Result("${second}"), out second);

        return hour + minute / 60 + second / 3600;

    }

    else return 0;

}



public static string DegreeToString(double degree)

{

    double minute = (degree - (int)degree) * 60;

    double second = (minute - (int)minute) * 60;

    return string.Format(

       "{0:#}°{1:#}′{2:#.00}″", 

       degree, 

       Math.Abs(minute), 

       Math.Abs(second));

}



private void button1_Click(object sender, EventArgs e)

{

    Console.WriteLine(DegreeToString(DegreeFromString("20°53'41''")));

    Console.WriteLine(DegreeToString(DegreeFromString("10°11'20.5''")));

    Console.WriteLine(

        DegreeToString(DegreeFromString("20°53'41''") - DegreeFromString("10°11'20.5''")));

    Console.WriteLine(

        DegreeToString(DegreeFromString("10°11'20.5''") - DegreeFromString("20°53'41''")));

}

输出：

21°54′41.00″
10°11′20.50″
11°42′20.50″
-11°42′20.50″

 from:http://www.csharpwin.com/csharpspace/9140r9620.shtml