private static IEnumerable <City> ReadCitiesFromJSON(CitiesSettings settings)
{
string path = Path.Combine(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location),
settings.Path);
return(JsonSerializer.Deserialize <IEnumerable <City> >(File.ReadAllText(path))
.Where(city => city.Country == "DE")); // Only the German cities are required
}
/// <summary>
/// Constructor
/// </summary>
/// <param name="citiesSettings">allows to configure the path to the cities.json</param>
/// <exception cref="ArgumentNullException">when citiesSettings == null</exception>
/// <exception cref="ArgumentException">when IsNullOrWhiteSpace(citiesSettings.Path)</exception>
public Cities(CitiesSettings citiesSettings)
{
if (citiesSettings == null)
{
throw new ArgumentNullException(nameof(citiesSettings));
}
if (string.IsNullOrWhiteSpace(citiesSettings.Path))
{
throw new ArgumentException("Path must not be nullOrWhitespace");
}
All = ReadCitiesFromJSON(citiesSettings);
}