How do I resolve "System.InvalidOperationException: The view 'Index' was not found&qu-CodePudding

I am doing an ASP.NET Core course online. One of the modules requires adding a Razor View to the application. Until I add the Razor view the application runs well. After I add it I get the following runtime error:

    System.InvalidOperationException: The view 'Index' was not found. The following locations were searched:
/Views/App/Index.cshtml
/Views/Shared/Index.cshtml
   at Microsoft.AspNetCore.Mvc.ViewEngines.ViewEngineResult.EnsureSuccessful(IEnumerable`1 originalLocations)
   at Microsoft.AspNetCore.Mvc.ViewFeatures.ViewResultExecutor.ExecuteAsync(ActionContext context, ViewResult result)
   at Microsoft.AspNetCore.Mvc.ViewResult.ExecuteResultAsync(ActionContext context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeNextResultFilterAsync>g__Awaited|29_0[TFilter,TFilterAsync](ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResultExecutedContextSealed context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.ResultNext[TFilter,TFilterAsync](State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeResultFilters()
--- End of stack trace from previous location where exception was thrown ---
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeNextResourceFilter>g__Awaited|24_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResourceExecutedContextSealed context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeFilterPipelineAsync()
--- End of stack trace from previous location where exception was thrown ---
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)
   at Microsoft.AspNetCore.Routing.EndpointMiddleware.<Invoke>g__AwaitRequestTask|6_0(Endpoint endpoint, Task requestTask, ILogger logger)
   at Microsoft.WebTools.BrowserLink.Net.BrowserLinkMiddleware.ExecuteWithFilterAsync(IHttpSocketAdapter injectScriptSocket, String requestId, HttpContext httpContext)
   at Microsoft.AspNetCore.Watch.BrowserRefresh.BrowserRefreshMiddleware.InvokeAsync(HttpContext context)
   at Microsoft.AspNetCore.Builder.Extensions.MapWhenMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Server.IIS.Core.IISHttpContextOfT`1.ProcessRequestAsync()
'iisexpress.exe' (CoreCLR: clrhost): Loaded 'C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App\3.1.29\Microsoft.AspNetCore.WebUtilities.dll'. Skipped loading symbols. Module is optimized and the debugger option 'Just My Code' is enabled.
'iisexpress.exe' (CoreCLR: clrhost): Loaded 'C:\Program Files\dotnet\shared\Microsoft.NETCore.App\3.1.29\System.Net.WebSockets.dll'. Skipped loading symbols. Module is optimized and the debugger option 'Just My Code' is enabled.
'iisexpress.exe' (CoreCLR: clrhost): Loaded 'C:\Program Files\dotnet\shared\Microsoft.NETCore.App\3.1.29\System.Security.Principal.Windows.dll'. Skipped loading symbols. Module is optimized and the debugger option 'Just My Code' is enabled.

As can be seen in the screenshot the View is in this location:

I had added the Razor NuGet:

This is my AppController code:

using Microsoft.AspNetCore.Mvc;

namespace DutchTreat.Controllers
{
    public class AppController : Controller
    {
        public IActionResult Index()
        {
            return View();
        }

    }
}

This is my Index.cshtml code:

@{
    ViewBag.Title = "Home Page";
}
<!DOCTYPE html>
<html>
<head>
    <title>Dutch Treat: @ViewBag.Title</title>

    <link href="~/css/site.css" rel="stylesheet" />

</head>
<body>
    <h2>@ViewBag.Title</h2>
    <div >
        <img src="~/img/VanGogh.jpg" />
        <h3>Mug</h3>
        <ul >
            <li>Price: $9.99</li>
            <li>Artist: Van Gogh</li>
            <li>Title:</li>
            <li>Description: Self-portrait</li>
        </ul>
        <button id="buyButton">Buy</button>

    </div>

    <div id="theForm">
        <form>
            <label>Your Name:</label>
            <br />
            <input />
            <br />
            <label>Email:</label>
            <br />
            <input type="email" />
            <br />
            <label>Subject:</label>
            <br />
            <input />
            <br />
            <label>Message:</label>
            <br />
            <textarea rows="4"></textarea>
            <br />
            <input type="submit" value="Send Message" />
        </form>
    </div>

    <!--<a href="lib/jquery/dist/jquery.min.map">lib/jquery/dist/jquery.min.map</a>
    <a href="lib/jquery/dist/jquery.slim.min.map">lib/jquery/dist/jquery.slim.min.map</a>-->

    <div>
        <div id="loginToggle">Login</div>
        <form >
            <div>
                <label>Username</label>
                <input />
            </div>
            <div>
                <label>Password</label>
                <input />
            </div>
            <div>
                <input type="checkbox" />
                <label>Remember me</label>
            </div>
            <div>
                <input type="submit" value="Login" />


            </div>
        </form>
    </div>

    <script src="~/lib/jquery/dist/jquery.min.js"></script>
    <script src="~/js/index.js"></script>

</body>
</html>

This is my Startup:

using DutchTreat.Controllers;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;


namespace DutchTreat
{
    public class Startup
    {
        // This method gets called by the runtime. Use this method to add services to the container.
        // For more information on how to configure your application, visit https://go.microsoft.com/fwlink/?LinkID=398940
        public void ConfigureServices(IServiceCollection services)
        {
            //services.AddControllersWithViews();
            services.AddControllersWithViews().AddRazorRuntimeCompilation();
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            //app.UseDefaultFiles();
            app.UseStaticFiles();
            app.UseRouting();
            app.UseEndpoints(cfg =>
                    {
                        cfg.MapControllerRoute("Default",
                                               "/{controller}/{action}/{id?}",
                                               new { controller = "App", action = "Index" });

                    });

            //If I understand correctly the bellow is for making an API avaialble without
            //having a webpage
            //app.UseEndpoints(endpoints =>
            //{
            //    endpoints.MapGet("/", async context =>
            //    {
            //        await context.Response.WriteAsync("Hello World!");
            //    });
            //});
        }
    }
}

The Index.cshtml properties build action is set to "content":

I have looked at various solutions to the problem and tried implementing them unsuccessfully. Would appreciate help

Thank you!

CodePudding user response：

Just as the error indicates,you should name the floder with Views instead of View