Error action extracted from CatalogController, because otherwise was violated Single Responsibility Principal, when even to generate an Error we will create Transient ICatalogService for each error.

src/Web/WebMVC/Controllers/CatalogController.cs

@@ -1,13 +1,10 @@
 using System;
-using System.Collections.Generic;
-using System.Linq;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.eShopOnContainers.WebMVC.ViewModels.Pagination;
 using Microsoft.eShopOnContainers.WebMVC.Services;
 using Microsoft.eShopOnContainers.WebMVC.ViewModels.CatalogViewModels;
 
-
 namespace Microsoft.eShopOnContainers.WebMVC.Controllers
 {
     public class CatalogController : Controller
@@ -42,8 +39,5 @@ namespace Microsoft.eShopOnContainers.WebMVC.Controllers
 
             return View(vm);
         }
-
-        public IActionResult Error() => View();
     }
-}
-
+}

src/Web/WebMVC/Controllers/ErrorController.cs

@@ -0,0 +1,9 @@
+using Microsoft.AspNetCore.Mvc;
+
+namespace WebMVC.Controllers
+{
+    public class ErrorController : Controller
+    {
+        public IActionResult Error() => View();
+    }
+}

src/Web/WebMVC/Startup.cs

@@ -102,7 +102,7 @@ namespace Microsoft.eShopOnContainers.WebMVC
             }
             else
             {
-                app.UseExceptionHandler("/Catalog/Error");
+                app.UseExceptionHandler("/Error");
             }
 
             app.UseSession();
@@ -145,6 +145,10 @@ namespace Microsoft.eShopOnContainers.WebMVC
                 routes.MapRoute(
                     name: "default",
                     template: "{controller=Catalog}/{action=Index}/{id?}");
+
+                routes.MapRoute(
+                    name: "defaultError",
+                    template: "{controller=Error}/{action=Error}");
             });
         }
     }