Google geometry Api in C#

问题

I have a point (latitude,longitude) ex : 33.959295,35.606100 and I'm looking for a way in c# to check if this point is on a specific route (a list of points or a polyline). I did some research and I found that isLocationOnEdge function contained within the Google Maps Geometry Library does exactly what I need but it is not available for c#. Here are some examples in other languages:

• Google Map Javascript API https://developers.google.com/maps/documentation/javascript/geometry#isLocationOnEdge.
• Android sample https://github.com/googlemaps/android-maps-utils/blob/master/library/src/com/google/maps/android/PolyUtil.java
• I found a c# library for gmaps google maps API for C# but it does not support the function isLocationOnEdge

Is there a way to do the required above in c#?

回答1:

Here is the implementation for IsLocationOnEdge For C#.

using System;
using System.Collections.Generic;
using System.Device.Location;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading;
using System.Threading.Tasks;

namespace TestConsoleApp
{
    class Program
    {
        static void Main(string[] args)
        {
            var path = new List<Location>
            {
                new Location(1,1),
                new Location(2, 2),
                new Location(3, 3),
            };
            var point = new Location(1.9, 1.5);
            bool isOnEdge = isLocationOnEdge(path, point);
            Console.ReadKey();
        }
        static bool isLocationOnEdge(List<Location> path, Location point, int tolerance = 2)
        {
            var C = new GeoCoordinate(point.Lat, point.Lng);
            for (int i = 0; i < path.Count - 1; i++)
            {
                var A = new GeoCoordinate(path[i].Lat, path[i].Lng);
                var B = new GeoCoordinate(path[i + 1].Lat, path[i + 1].Lng);
                if (Math.Round(A.GetDistanceTo(C) + B.GetDistanceTo(C), tolerance) == Math.Round(A.GetDistanceTo(B), tolerance))
                {
                    return true;
                }
            }
            return false;
        }
    }
    class Location
    {
        public Location(double Lat, double Lng)
        {
            this.Lat = Lat;
            this.Lng = Lng;
        }
        public double Lat { get; set; }
        public double Lng { get; set; }
    }
}

References:

Check is a point (x,y) is between two points drawn on a straight line Calculating Distance between two Latitude and Longitude GeoCoordinates

来源：https://stackoverflow.com/questions/50988633/google-geometry-api-in-c-sharp