Url.Action() 在 ASP.NET 核心 3.0 中返回 null

Question

After migrating to the ASP.NET Core 3.0 . The Url.Action() returns null for valid action, controller. This worked in ASP.NET core 2.2

The action name does not contain async as explained in Microsoft Doc for migration to core 3.0

Configure method

   app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllerRoute(
                    name: "default",
                    pattern: "{controller=Home}/{action=Index}/{id?}");
            });

ConfigureServices method

        services.AddControllersWithViews()
            .AddControllersAsServices()
            .AddSessionStateTempDataProvider()
            .AddMvcLocalization();

Eg

    // url is null
    string url = Url.Action("DeleteAccount", "Manage", null);

What am i missing?

Answer 1

I have met same question as yours. I think you haven't AddNewtonsoftjson in your configureServices function. Try to add it.

  <PackageReference Include="Microsoft.AspNetCore.Mvc.NewtonsoftJson" Version="3.0.0" /> 

 services.AddControllersWithViews().AddNewtonsoftJson();