authentication in blazor server side code example

Example 1: blazor server side authentication with identityserver4

/*               User Info in Razor ComponentsPermalink
In a Blazor server-side application, authenticated user information is available 
to Razor components by injecting the AuthenticationStateProvider. 
We’ll modify Index.razor to show some information about the authenticated user. */

@page "/"
@inject AuthenticationStateProvider AuthState

<h1>Hello, @Username</h1>

<p>Welcome to your new app.</p>

<p>
    <a href="/Logout">Logout</a>
</p>

@code
{
    private string Username = "Anonymous User";

    protected override async Task OnInitializedAsync()
    {
        var state = await AuthState.GetAuthenticationStateAsync();
        
        Username =

Example 2: blazor server side authentication with identityserver4

<Router AppAssembly="@typeof(Program).Assembly">
    <Found Context="routeData">
        <AuthorizeRouteView RouteData="@routeData" DefaultLayout="@typeof(MainLayout)">
            <NotAuthorized>
                <h1>Sorry</h1>
                <p>You're not authorized to reach this page.</p>
                <p>You may need to log in as a different user.</p>
            </NotAuthorized>
            <Authorizing>
                <h1>Authentication in progress</h1>
                <p>Only visible while authentication is in progress.</p>
            </Authorizing>
        </AuthorizeRouteView>
    </Found>
    <NotFound>
        <CascadingAuthenticationState>
            <LayoutView Layout="@typeof(MainLayout)">
                <h1>Sorry</h1>
                <p>Sorry, there's nothing at this address.</p>
            </LayoutView>
        </CascadingAuthenticationState>
    </NotFound>
</Router>