ReverseGeocodeLib 1.2.2

ReverseGeocodeLib

Usage

Below is a basic example showing how to load the embedded country and city data and use the library to find the country and city for a given latitude/longitude. You must call the Load...Async methods before calling any Find... methods.

using System;
using System.Threading.Tasks;
using ReverseGeocodeLib;

class Program
{
    static async Task Main(string[] args)
    {
        // Load embedded binary data (these should be embedded as resources)
        await ReverseGeocodeService.LoadCountriesAsync();
        await ReverseGeocodeService.LoadCitiesAsync();

        // Specify coordinates (latitude, longitude). Example: London
        double latitude = 51.5074;
        double longitude = -0.1278;

        // Find country and city
        var countries = ReverseGeocodeService.FindCountry(latitude, longitude);
        var cities = ReverseGeocodeService.FindCity(latitude, longitude);

        // The methods return a list of tuples (Id, Name)
        if (countries.Count > 0)
            Console.WriteLine($"Country: {countries[0].Name} (Id: {countries[0].Id})");
        else
            Console.WriteLine("No country match.");

        if (cities.Count > 0)
            Console.WriteLine($"City: {cities[0].Name} (Id: {cities[0].Id})");
        else
            Console.WriteLine("No city match.");

        // With an enclave the country could have more than 1 result, no way to tell which is correct
        if (country == null || country.Count == 0)
        {
            Console.WriteLine("Country: Not found");
        }
        else
        {
            if (country.Count > 1)
                Console.WriteLine($"Countries: {country[0].Item2} or {country[1].Item2}");
            else
                Console.WriteLine($"Country: {country[0].Item2}");
        }
    }
}

Other available lookups:

• ReverseGeocodeService.LoadUSAStatesAsync() and FindUSAState(latitude, longitude)
• ReverseGeocodeService.LoadFranceDepartmentsAsync() and FindFranceDepartment(latitude, longitude)
• ReverseGeocodeService.LoadFranceRegionsAsync() and FindFranceRegion(latitude, longitude)
• ReverseGeocodeService.LoadUKCountiesAsync() and FindUKCounty(latitude, longitude)
• ReverseGeocodeService.LoadNetherlandsProvincesAsync() and FindNetherlandsProvince(latitude, longitude)

Notes:

• If no area matches the provided location, you’ll get an empty list.
• The library uses a point-in-polygon algorithm to test if the point is inside an area’s polygon(s).
• Embedded data files are expected as assembly resources with names such as {AssemblyName}.Data.countries.bin, {AssemblyName}.Data.cities.bin, etc.
  • Confirm your .csproj includes:

    <ItemGroup>
      <EmbeddedResource Include="Data\countries.bin" />
      <EmbeddedResource Include="Data\cities.bin" />
    
    </ItemGroup>
    
    

Acknowledgements to

https://github.com/InquisitorJax/Wibci.CountryReverseGeocode for the orignal project

https://simplemaps.com for map data