How do you handle 404 pages in Blazor?

The NotFound template section in the App.razor can be used to handling 404 pages. The router shows this content if it hits a route that is not available, which is a 404 page.

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

    <NotFound> 
        <LayoutView Layout="@typeof(MainLayout)"> 
            <p>Handled 404 page</p> 
        </LayoutView> 
    </NotFound> 
</Router> 

Create a component Page/Error.razor to display the 404 contents. For more information, read about Blazor routing.