Action Method in ASP.NET Core, IActionResult in ASP.NET Core, ActionResult MVC

 using Microsoft.AspNetCore.Mvc;

namespace ControllersAndActions.Controllers

{

    public class HomeController : Controller

    {

        public IActionResult Index()

        {

            return View();  //ViewResult, PartialViewResult, JsonResult etc

        }

        public string Display()

        {

            return "Welcome To Programentor";

        }

        public int DisplayId(int id)

        {

            return id;

        }

    }

}

Above File is ControllersAndActions\Controllers\HomeController.cs File

@{

    ViewData["Title"] = "Index";

}

<h1>Index</h1>

Above File is ControllersAndActions\Views\Home\Index.cshtml File

namespace ControllersAndActions

{

    public class Program

    {

        public static void Main(string[] args)

        {

            var builder = WebApplication.CreateBuilder(args);

            builder.Services.AddControllersWithViews();

            var app = builder.Build();

            app.MapControllerRoute(

                name:"default",

                pattern:"{controller=Home}/{action=Index}/{id?}"

                );

            //app.MapGet("/", () => "Hello World!");

            app.Run();

        }

    }

}

Above File is ControllersAndActions\Program.cs File