Using 'UseMvc' to configure MVC is not supported while using Endpoint Routing

Question

I had an Asp.Net core 2.2 project.

Recently, I changed the version from .net core 2.2 to .net core 3.0 Preview 8. After this change I see this warning message:

using 'UseMvc' to configure MVC is not supported while using Endpoint Routing. To continue using 'UseMvc', please set 'MvcOptions.EnableEndpointRouting = false' inside 'ConfigureServices'.

I understand that by setting EnableEndpointRouting to false I can solve the issue, but I need to know what is the proper way to solve it and why Endpoint Routing does not need UseMvc() function.

about proper way: this doc https://learn.microsoft.com/en-us/aspnet/core/migration/22-to-30?view=aspnetcore-2.2&tabs=visual-studio#update-routing-startup-code states "migrate the app to Endpoint Routing if possible" — dvitel, Aug 28 '19 at 02:34

Sergii Zhuravskyi · Answer 1 · 2020-01-29T15:49:41.210

I found the solution, in the following official documentation "Migrate from ASP.NET Core 2.2 to 3.0":

There are 3 approaches:

Replace UseMvc or UseSignalR with UseEndpoints.

In my case, the result looked like that

  public class Startup
{

    public void ConfigureServices(IServiceCollection services)
    {
        //Old Way
        services.AddMvc();
        // New Ways
        //services.AddRazorPages();
    }


    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        if (env.IsDevelopment())
        {
            app.UseDeveloperExceptionPage();
        }

        app.UseStaticFiles();
        app.UseRouting();
        app.UseCors();

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

    }
}

OR
2. Use AddControllers() and UseEndpoints()

public class Startup
{

    public void ConfigureServices(IServiceCollection services)
    {
        services.AddControllers();
    }


    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        if (env.IsDevelopment())
        {
            app.UseDeveloperExceptionPage();
        }

        app.UseStaticFiles();
        app.UseRouting();
        app.UseCors();

        app.UseEndpoints(endpoints =>
        {
            endpoints.MapControllers();
        });

    }
}

OR
3. Disable endpoint Routing. As the exception message suggests and as mentioned in the following section of documentation: use mvcwithout endpoint routing


services.AddMvc(options => options.EnableEndpointRouting = false);
//OR
services.AddControllers(options => options.EnableEndpointRouting = false);

This works in asp.net core 3.0 and I can use this add web API easily — Tony Dong, Oct 17 '19 at 23:05
It's recommended (on that page) to use `services.AddRazorPages();` instead of `services.AddMvc();` — BurnsBA, Oct 29 '19 at 12:57
This is a good solution if you're going through the [first mvc tutorial](https://learn.microsoft.com/en-us/aspnet/core/tutorials/first-mvc-app) and upgrade from core2.1 to core3.0. This solved my issue immediately, thanks! — Spencer Pollock, Nov 17 '19 at 23:29
So they basically just slightly changed the syntax from UseMvc() to UseEndpoints(). — Steve Smith, May 24 '22 at 15:47
I needed to adapt some ASP.NET Core 2.2 example code => ASP.NET 5. OLD: `app.UseMvc(routes => {...});` NEW: `app.UseEndpoints(endpoints => {...});`. In other words: Option 1 worked like a charm! Thank you! Too bad this isn't the "accepted" reply. — paulsm4, Oct 15 '22 at 19:19

score 91 · Answer 2 · edited Jan 13 '20 at 10:48

91

This worked for me (add in Startup.cs > ConfigureServices method):

services.AddMvc(option => option.EnableEndpointRouting = false)

edited Jan 13 '20 at 10:48

Arsen Khachaturyan

7,904
4
42
42

answered Nov 08 '19 at 19:16

Bonaventura72

1,021
6
3

3

Simple answer, but Great answer! – Rohan Rao Jan 13 '20 at 10:29
1

I would argue about the usefulness of this answer. This answers how not why... – Tomasz Juszczak Sep 23 '22 at 17:43

score 44 · Accepted Answer · answered Aug 29 '19 at 08:13

but I need to know what is the proper way to solve it

In general, you should use EnableEndpointRouting instead of UseMvc, and you could refer Update routing startup code for detail steps to enable EnableEndpointRouting.

why Endpoint Routing does not need UseMvc() function.

For UseMvc, it uses the IRouter-based logic and EnableEndpointRouting uses endpoint-based logic. They are following different logic which could be found below:

if (options.Value.EnableEndpointRouting)
{
    var mvcEndpointDataSource = app.ApplicationServices
        .GetRequiredService<IEnumerable<EndpointDataSource>>()
        .OfType<MvcEndpointDataSource>()
        .First();
    var parameterPolicyFactory = app.ApplicationServices
        .GetRequiredService<ParameterPolicyFactory>();

    var endpointRouteBuilder = new EndpointRouteBuilder(app);

    configureRoutes(endpointRouteBuilder);

    foreach (var router in endpointRouteBuilder.Routes)
    {
        // Only accept Microsoft.AspNetCore.Routing.Route when converting to endpoint
        // Sub-types could have additional customization that we can't knowingly convert
        if (router is Route route && router.GetType() == typeof(Route))
        {
            var endpointInfo = new MvcEndpointInfo(
                route.Name,
                route.RouteTemplate,
                route.Defaults,
                route.Constraints.ToDictionary(kvp => kvp.Key, kvp => (object)kvp.Value),
                route.DataTokens,
                parameterPolicyFactory);

            mvcEndpointDataSource.ConventionalEndpointInfos.Add(endpointInfo);
        }
        else
        {
            throw new InvalidOperationException($"Cannot use '{router.GetType().FullName}' with Endpoint Routing.");
        }
    }

    if (!app.Properties.TryGetValue(EndpointRoutingRegisteredKey, out _))
    {
        // Matching middleware has not been registered yet
        // For back-compat register middleware so an endpoint is matched and then immediately used
        app.UseEndpointRouting();
    }

    return app.UseEndpoint();
}
else
{
    var routes = new RouteBuilder(app)
    {
        DefaultHandler = app.ApplicationServices.GetRequiredService<MvcRouteHandler>(),
    };

    configureRoutes(routes);

    routes.Routes.Insert(0, AttributeRouting.CreateAttributeMegaRoute(app.ApplicationServices));

    return app.UseRouter(routes.Build());
}

For EnableEndpointRouting, it uses EndpointMiddleware to route the request to the endpoints.

score 20 · Answer 4 · answered Jul 02 '20 at 10:12

The issue I found to be due to updates on the .NET Core framework. The latest .NET Core 3.0 released version requires explicit opt-in for using MVC.

This issue is most visible when one tries to migrate from older .NET Core(2.2 or preview 3.0 version) to .NET Core 3.0

If migrating from 2.2 to 3.0, please use the below code to fix the issue.

services.AddMvc(options => options.EnableEndpointRouting = false);

If using .NET Core 3.0 template,

services.AddControllers(options => options.EnableEndpointRouting = false);

ConfigServices method after fix as below,

Thank You

Md. Nazmul Nadim · Answer 5 · 2021-04-07T13:32:18.547

13

Endpoint Routing is disabled by default on ASP.NET 5.0

Just configure as in Startup

    public void ConfigureServices(IServiceCollection services)
    {
        services.AddMvc(options => options.EnableEndpointRouting = false);
    }

This worked for me

edited Apr 07 '21 at 13:32

answered Apr 06 '21 at 15:31

Md. Nazmul Nadim

207
2
5

score 10 · Answer 6 · edited Apr 27 '20 at 20:24

10

You can use : in ConfigureServices method:

services.AddControllersWithViews();

And for Configure method:

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

edited Apr 27 '20 at 20:24

Unheilig

16,196
193
68
98

answered Apr 27 '20 at 19:11

NHARI Med

151
1
7

This worked well for me, I needed to add `app.UseRouting();` though. – jpo Jul 07 '22 at 11:13

score 7 · Answer 7 · edited Feb 07 '21 at 00:07

public class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {
        //Old Way
        services.AddMvc();
        // New Ways
        //services.AddRazorPages();
    }

    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        if (env.IsDevelopment())
        {
            app.UseDeveloperExceptionPage();
        }

        app.UseStaticFiles();
        app.UseRouting();
        app.UseCors();

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

This works also in .Net Core 5

What is the difference with [NHARI Med](https://stackoverflow.com/a/61466585/52277) answer ? — Michael Freidgeim, Aug 04 '22 at 22:40

score 6 · Answer 8 · answered Sep 18 '21 at 23:17

-> In ConfigureServices method - Startup.cs

        //*****REGISTER Routing Service*****
        services.AddMvc();
        services.AddControllers(options => options.EnableEndpointRouting = false);

-> In Configure Method - Startup.cs

       //*****USE Routing***** 
        app.UseMvc(Route =>{
            Route.MapRoute(
                name:"default",
                template: "{Controller=Name}/{action=Name}/{id?}"
            );
        });

score 5 · Answer 9 · edited May 12 '22 at 11:16

5

For DotNet Core 3.1

Use below

File : Startup.cs

public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{         

    if (env.IsDevelopment())
    {
        app.UseDeveloperExceptionPage();
    }
       
    app.UseHttpsRedirection();
    app.UseRouting();
    app.UseAuthentication();
    app.UseHttpsRedirection();
    app.UseEndpoints(endpoints =>
    {
        endpoints.MapControllers();
    });
}

edited May 12 '22 at 11:16

Ciarán Bruen

5,221
13
59
69

answered Jun 06 '20 at 23:03

sagar charde

59
1
3

1

What to do with all the services configuration lines? – Fanchi Aug 10 '20 at 13:15

score 0 · Answer 10 · answered Aug 08 '21 at 03:40

0

This worked for me

 services.AddMvc(options => options.EnableEndpointRouting = false); or 
 OR
 services.AddControllers(options => options.EnableEndpointRouting = false);

answered Aug 08 '21 at 03:40

user9552541

9
1

What is the difference with option 3 in top [Sergii Zhuravskyi answer](https://stackoverflow.com/a/58267385/52277)? Yo can just upvote an existing answer – Michael Freidgeim Aug 04 '22 at 22:43

score -5 · Answer 11 · answered Oct 16 '19 at 05:57

-5

Use Below Code

app.UseEndpoints(endpoints =>
            {
                endpoints.MapDefaultControllerRoute();
                endpoints.MapGet("/", async context =>
                {
                    await context.Response.WriteAsync("Hello World!");
                });
            });

answered Oct 16 '19 at 05:57

Mandy

17
1

It would help if you explained *how* this code solves the problem. – Robert Columbia Oct 23 '19 at 13:59
1

Simply posting code is not a sufficient answer. Please explain what/why/how this code will answer the question. – nurdyguy Oct 23 '19 at 19:40
1

this is just boiler plate that comes out of the box and doesnt actually help the user with that they are adter – Simon Price Dec 24 '19 at 11:07
The above code will throw an error since it does not have {id? } as optional parameter app.UseEndpoints(endpoints => { endpoints.MapControllerRoute("default", "{controller=Home}/{action=Index}/ {id?}"); }); – user3920526 Jan 07 '23 at 14:41

Using 'UseMvc' to configure MVC is not supported while using Endpoint Routing

11 Answers11

Linked