CaritasPWA/Shared/Services/OSM/NominatimService.cs

using cwebplusApp.Shared.Models;
using Json.Net;
using System;
using System.Globalization;
using System.Net.Http;
using System.Threading.Tasks;

namespace cwebplusApp.Shared.Services {
    public class NominatimService {

        public static async Task<NominatimReverseAddress> GetAddressForCoordinates(double latitude, double longitude) {
            string lat = latitude.ToString("0.0000000000", CultureInfo.InvariantCulture);
            string lng = longitude.ToString("0.0000000000", CultureInfo.InvariantCulture);

            HttpClient httpClient = new() { BaseAddress = new Uri("https://nominatim.openstreetmap.org/") };
            try {
                HttpResponseMessage httpResult = await httpClient.GetAsync(string.Format("reverse?format=json&lat={0}&lon={1}", lat, lng));

                if (httpResult.StatusCode == System.Net.HttpStatusCode.OK) {
                    NominatimReverseAddress addressDto = JsonNet.Deserialize<NominatimReverseAddress>(await httpResult.Content.ReadAsStringAsync());
                    return addressDto;
                }
                return null;

            } catch (Exception) {
                return null;
            }
        }
    }
}