Controller dotnetCore class not found

Question

I'm using .net core and have added some 4.5 libraries to my project. This works fine. But Visual Studio 2015 can't seem to find the "Controller" (which is a ASP.net core class) class.

My project.json file looks like this:

 {
  "dependencies": {
    "Microsoft.AspNetCore.Mvc": "1.0.1",
    "Microsoft.AspNetCore.Server.IISIntegration": "1.0.0",
    "Microsoft.AspNetCore.Server.Kestrel": "1.0.0",
    "Microsoft.Extensions.Configuration.EnvironmentVariables": "1.0.0",
    "Microsoft.Extensions.Configuration.FileExtensions": "1.0.0",
    "Microsoft.Extensions.Configuration.Json": "1.0.0",
    "Microsoft.Extensions.Logging": "1.0.0",
    "Microsoft.Extensions.Logging.Console": "1.0.0",
    "Microsoft.Extensions.Logging.Debug": "1.0.0",
    "Microsoft.Extensions.Options.ConfigurationExtensions": "1.0.0",
    "Microsoft.AspNetCore.StaticFiles": "1.0.0-rc2-final"
  },

  "tools": {
    "Microsoft.AspNetCore.Server.IISIntegration.Tools": "1.0.0-preview2-final"
  },

  "frameworks": {
    "net452": {
      "dependencies": {
        "ClassLibrary1": {
          "target": "project"
        },
        "ClassLibrary2": {
          "target": "project"
        }
      }
    }
  },

  "buildOptions": {
    "emitEntryPoint": true,
    "preserveCompilationContext": true
  },

  "runtimeOptions": {
    "configProperties": {
      "System.GC.Server": true
    }
  },

  "publishOptions": {
    "include": [
      "wwwroot",
      "Views",
      "Areas/**/Views",
      "appsettings.json",
      "web.config"
    ]
  },

  "scripts": {
    "postpublish": [ "dotnet publish-iis --publish-folder %publish:OutputPath% --framework %publish:FullTargetFramework%" ]
  }
}

When declaring a controller, the "AspNetCore.Mvc" package is not found. And the "Controller" class is not found.

using Microsoft.AspNetCore.Mvc;
namespace WebInterface.Backend
{
    public class AppController : Controller
    {
    }
}

I'm suspecting that there is something wrong with my project.json but can't seem to find the problem. Any suggestions?

Update:

It seems to work, i can build the project but my inteli sense can't find the class, all the includes (system, Mvc) are not found. But when i build it gives no errors. Can also run the project. Any Idea's?

Answer 1

In my case (ASP.NET Core 3.1) it was that startup.cs did not contain MapControllerRoute()

Adding MapControllerRoute() fixed it:

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

Taken from add a controller to an ASP.NET Core MVC app

Answer 2

I know this is late, but hopefully it helps someone...

I had a similar issue, my problem was that I named my folder "Controller" instead of "Controllers"

Once I corrected the folder name, everything worked as expected.

Answer 3

try running this command in cmd in the directory where the project.json file is:

dotnet restore