Implementing Azure AD B2C Authentication in .NET 8 Blazor Project (RenderMode: InteractiveAuto)

Question

I'm working on a .NET 8 Blazor project and I'm trying to implement Azure AD B2C authentication. According to Microsoft's documentation, I'm using RemoteAuthenticatorView. It works fine in WebAssembly mode, but I'm encountering issues when using "Interactive Auto".

When I use "Interactive Auto", I get the following error:

Cannot provide a value for property ‘AuthenticationService’ on type ‘Microsoft.AspNetCore.Components.WebAssembly.Authentication.RemoteAuthenticatorView’. There is no registered service of type ‘Microsoft.AspNetCore.Components.WebAssembly.Authentication.IRemoteAuthenticationService`1[Microsoft.AspNetCore.Components.WebAssembly.Authentication.RemoteAuthenticationState]’

In an attempt to resolve this, I added builder.Services.AddApiAuthorization(); to my code. However, this resulted in another error:

Unable to cast object of type ‘Microsoft.AspNetCore.Components.Server.ServerAuthenticationStateProvider’ to type ‘Microsoft.AspNetCore.Components.WebAssembly.Authentication.IRemoteAuthenticationService`1[Microsoft.AspNetCore.Components.WebAssembly.Authentication.RemoteAuthenticationState]’

I'm looking for guidance on how to resolve these errors and successfully implement Azure AD B2C authentication in my Blazor project. Any help would be greatly appreciated.

Answer 1

The error message suggests there might be an issue with the AuthenticationStateProvider being used. Make sure you are using the correct provider for Blazor WebAssembly. It should be RemoteAuthenticationStateProvider.

builder.Services.AddScoped<AuthenticationStateProvider, RemoteAuthenticationStateProvider>();