Bilder zur Frage können hochgeladen werden;

MultipleChoiceTrainer/Views/Shared/_Layout.cshtml

@@ -41,10 +41,15 @@
     <script src="~/lib/jquery/dist/jquery.min.js"></script>
     <script src="~/lib/bootstrap/dist/js/bootstrap.bundle.min.js"></script>
     <script src="~/js/site.js" asp-append-version="true"></script>
+    <script src="~/js/bs-custom-file-input.min.js"></script>
     <script>
         $(function () {
             $('[data-toggle="tooltip"]').tooltip()
         })
+
+        $(document).ready(function () {
+            bsCustomFileInput.init()
+        })
     </script>
     @RenderSection("Scripts", required: false)
 </body>