升级到.net核心3.0

Question

We have recently upgraded our asp.net core 2.2 to 3.0 but cant figure out the problem we are having right now...

When I start up the webproject, I get an exception on "MapControllers":

ReflectionTypeLoadException: Unable to load one or more of the requested types. Could not load type 'Microsoft.AspNetCore.Mvc.ViewFeatures.Internal.SaveTempDataFilter' from assembly 'Microsoft.AspNetCore.Mvc.ViewFeatures, Version=3.0.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'.

It looks like something is using SaveTempDataFilter from "Microsoft.AspNetCore.Mvc.ViewFeatures" that doesnt exists anymore, or am I wrong?

Any help in the right direction is appreciated.

      app.UseEndpoints(endpoints => {
                endpoints.MapControllers();
                endpoints.MapAreaControllerRoute("admin", "admin", "Admin/{controller}/{action=Index}/{id?}");
                endpoints.MapControllerRoute("default", "{controller=Schedule}/{action=Index}/{id?}");
            });

Program.cs

          var host = Host.CreateDefaultBuilder(args)
                .ConfigureWebHostDefaults(webBuilder =>
                {
                    webBuilder
                    .UseContentRoot(Directory.GetCurrentDirectory())
                    .UseKestrel((context, options) =>
                    {
                        options.AddServerHeader = false;
                    })
                    .UseIIS()
                    .UseIISIntegration()
                    .UseStartup<Startup>();
                })
                .Build();

            host.Run();

Answer 1

I found the problem.

We where using a nuget package "AspNetCore.Mvc.CookieTempData" who tried to use something in "Microsoft.AspNetCore.Mvc.ViewFeatures" which did not exist anymore.

Removing this package solved it.