/// <summary>
/// Localizes all convention-based routes in the <paramref name="routeCollection"/> with a custom configured
/// <see cref="LocalizationOptions"/> instance. This method should be called after all routes have been configured.
/// </summary>
/// <param name="routeCollection">The collection containing all the routes of the ASP.NET MVC application.</param>
/// <param name="options">A callback to configure the default <see cref="LocalizationOptions"/> instance.</param>
/// <exception cref="ArgumentException"><paramref name="routeCollection"/> is null.</exception>
public static void Localize(this RouteCollection routeCollection, Action <LocalizationOptions> options)
{
if (routeCollection == null)
{
throw new ArgumentNullException(nameof(routeCollection));
}
// Create and initialize a new LocalizationOptions instance
var localizationOptions = new LocalizationOptions();
options?.Invoke(localizationOptions);
localizationOptions.Dictionary.Init(localizationOptions.MvcTopologyProvider);
// Create separate collection for all named and unnamed routes
var namedMap = typeof(RouteCollection).GetField("_namedMap", BindingFlags.NonPublic | BindingFlags.Instance).GetValue(routeCollection)
as Dictionary <string, RouteBase>
?? throw new InvalidOperationException($"There is no _namedMap field in the {nameof(RouteCollection)} class.");
var unnamedRoutes = routeCollection.Except(namedMap.Values);
// And combine them to a common list with their nullable names as key
var routes = namedMap.Concat(unnamedRoutes.Select(route => new KeyValuePair <string, RouteBase>(null, route))).ToList();
// Iterate through all available routes
foreach (var routeItem in routes)
{
// Which has the type Route
if ((routeItem.Value is Route route) && (route.GetType() == typeof(Route)))
{
// Create a new LocalizedRoute proxy
string routeName = routeItem.Key;
var localizedRoute = new LocalizedRoute(route, localizationOptions.Dictionary);
// Replace the original route with this new one
int index = routeCollection.IndexOf(route);
routeCollection[index] = localizedRoute;
if (!string.IsNullOrEmpty(routeName))
{
namedMap[routeName] = localizedRoute;
}
}
}
}
