Routing

For the default Blazor projects—those generated by Visual Studio or thedotnettool—you will notice that there is no entry page, noindex.html, no controller, and no default Razor page. Because of that, when you access your app through your browser, you will end up on the fallback page, the one that I mentioned in the Implementing Blazor Server section. If you look at this page, you will notice that it is essentially a simple Razor page with a <component>tag helper —one that was just introduced in .NET Core 3. This tag helper is rendering theAppcomponent, and if you look inside of the App.razor file, you will find some weird markup—something like this:

<Router AppAssembly="@typeof(Program).Assembly">
   <Found Context="routeData">
        <RouteView RouteData="@routeData" DefaultLayout=
        "@typeof(MainLayout)" />
    </Found>
   <NotFound>
       <LayoutView...