URL Globalization in asp.net core 5 - asp.net-core

Question

I am about to change my asp.net core Globalization by URL.
Just like Microsoft official site:
https://www.microsoft.com/zh-cn/ is for the Chinese version.
https://www.microsoft.com/en-us/ is for the English version.
What I want to do is something different:
https://www.aaa.com/zh-hans/index.html is for the Chinese version.
https://www.aaa.com/en/index.html is for the English version.
As you see above, I need to add a .html suffix also.
I found some tutorials on google.
Here is my code:
public void ConfigureServices(IServiceCollection services)
{
services.AddLocalization(options => options.ResourcesPath = "Resources");
services.AddMvc().AddViewLocalization(Microsoft.AspNetCore.Mvc.Razor.LanguageViewLocationExpanderFormat.Suffix,
options => options.ResourcesPath = "Resources").AddSessionStateTempDataProvider();
}
public void Configure(IApplicationBuilder app)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
else
{
app.UseExceptionHandler("/Home/Error");
// The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
//app.UseHsts();
}
app.UseRouting();
app.UseStaticFiles();
var SupportedCultures = new List<CultureInfo> {
new CultureInfo("en"),
new CultureInfo("zh-Hans"),
new CultureInfo("zh-Hant")
};
var options = new RequestLocalizationOptions
{
DefaultRequestCulture = new RequestCulture("en"),
SupportedCultures = SupportedCultures,
SupportedUICultures = SupportedCultures,
};
app.UseRequestLocalization(options);
var requestProvider = new RouteDataRequestCultureProvider();
options.RequestCultureProviders.Insert(0, requestProvider);
app.UseEndpoints(endpoints =>
{
endpoints.MapControllerRoute(name: "default", pattern: "{culture}/{controller=Home}/{action=Index}.html", defaults: new { culture = "en", controller = "Home", action = "Index" });
});
}
However, after the website ran, it reports an error:
An unhandled exception occurred while processing the request.
AmbiguousMatchException: The request matched multiple endpoints. Matches:
Sample.Controllers.HomeController.Index (Sample)
Sample.Controllers.HomeController.Error (Sample)
Sample.Controllers.HomeController.Privacy (Sample)
Microsoft.AspNetCore.Routing.Matching.DefaultEndpointSelector.ReportAmbiguity(CandidateState[] candidateState)
It seems that's because I added a .html suffix in MapControllerRoute.
I am not quite sure whether my code is right for most of the tutorial is for asp.net core 2 or even for asp.net core 1. Most of the code now not work in asp.net core 5 anymore.
What's wrong with my code? Thank you.
HomeController:
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Logging;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Threading.Tasks;
using Sample.Models;
namespace Sample.Controllers
{
public class HomeController : Controller
{
private readonly ILogger<HomeController> _logger;
public HomeController(ILogger<HomeController> logger)
{
_logger = logger;
}
public IActionResult Index()
{
return View();
}
public IActionResult Privacy()
{
return View();
}
[ResponseCache(Duration = 0, Location = ResponseCacheLocation.None, NoStore = true)]
public IActionResult Error()
{
return View(new ErrorViewModel { RequestId = Activity.Current?.Id ?? HttpContext.TraceIdentifier });
}
}
}