NavigationManager.NavigateTo has no effect if called after a aynchronous method in OnIntializedAsync, in SSR mode

[SebastianToet]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

Since .NET 10 Preview 4, where NavigationManager.NavigateTo no longer throws a NavigationException, NavigateTo no longer has any effect in SSR mode, if called after an aynchronous method call in OnInitializedAsync.

Expected Behavior

NavigationManager.NavigateTo navigates to the specified route.

Steps To Reproduce

Doesn't work:

@inject NavigationManager NavigationManager
@code {
    protected override async Task OnInitializedAsync()  
    {
           await Task.Delay(1000);
           NavigationManager.NavigateTo("any-route"); //Does nothing
    }  
}

Works correctly:

@inject NavigationManager NavigationManager
@code {
    protected override async Task OnInitializedAsync()  
    {
           NavigationManager.NavigateTo("any-route"); //Works correctly
           await Tasl.Delay(1000);
    }  

Exceptions (if any)

No response

.NET Version

10.0.100-preview.5.25277.114

Anything else?

No response

[javiercn]

@SebastianToet thanks for contacting us.

I believe this was potentially addressed in preview6. @ilonatommy can you confirm?

[ilonatommy]

I tested p5, from default blazor SSR template and it does work - it navigates to "any-route" and because it's not found, re-execution gets activated and the not found page is rendered. New and old way of working behave same (in p5: Microsoft.AspNetCore.Components.Endpoints.NavigationManager.EnableThrowNavigationException with true and false).
I think I will need the full repro, could you please post it?

[ilonatommy]

My bad: in p5 template there's no re-execution, so for the not-found page rendering behavior you would have to add in Program.cs:

app.UseStatusCodePagesWithReExecute("/not-found", createScopeForErrors: true);

However, it does not have any impact on navigation.

[tharlab]

hi thanks this fix my problem, InvalidOperationException: 'RemoteNavigationManager' already initialized.
now i can using NavigationManager.NotFound(); on my component
also global handler app.UseStatusCodePagesWithReExecute() enabled on Program.cs

My bad: in p5 template there's no re-execution, so for the not-found page rendering behavior you would have to add in Program.cs:

app.UseStatusCodePagesWithReExecute("/not-found", createScopeForErrors: true);

However, it does not have any impact on navigation.

[tharlab]

My bad: in p5 template there's no re-execution, so for the not-found page rendering behavior you would have to add in Program.cs:

app.UseStatusCodePagesWithReExecute("/not-found", createScopeForErrors: true);

However, it does not have any impact on navigation.

edited:my bad on my flow, figured out now

hi @ilonatommy again it doesnot work in net10-RC.1
app.UseStatusCodePagesWithReExecute("/not-found", createScopeForErrors: true);
with NavigationManager.NotFound(); any solution??

An unhandled exception occurred while processing the request.
InvalidOperationException: requires a non-null value for the parameter 'RouteData'.
Microsoft.AspNetCore.Components.Routing.FocusOnNavigate.OnParametersSet()

oh additional iam using CascadingValue to custom my layout, seem RouteData null on NotFound page

        <CascadingValue Value="@routeData">
            <RouteView RouteData="@routeData" DefaultLayout="@typeof(MyLayout)" />
        </CascadingValue>

      [CascadingParameter]RouteData RouteData { get; set; }

eg.
https://stackoverflow.com/a/59900834/11934679

[ilonatommy]

@tharlab, thank you for your report. This might be a different problem, please file a separate issue with a reproduction repository.