Login page for Auth0

login.cshtml.cs

using Microsoft.AspNetCore.Authentication;
using Auth0.AspNetCore.Authentication;
using Microsoft.AspNetCore.Mvc.RazorPages;

namespace MyApplication.Pages
{
    public class LoginModel : PageModel
    {
        public async Task OnGet(string redirectUri, string? invitation = null, string? organization = null)
        {
            var authenticationPropertiesBuilder = new LoginAuthenticationPropertiesBuilder()
                .WithRedirectUri(redirectUri ?? "/home");

            if (invitation != null)
            {
                authenticationPropertiesBuilder.WithInvitation(invitation);
            }

            if (organization != null)
            {
                authenticationPropertiesBuilder.WithOrganization(organization);
            }

            var authenticationProperties = authenticationPropertiesBuilder.Build();

            await HttpContext.ChallengeAsync(Auth0Constants.AuthenticationScheme, authenticationProperties);
        }
    }
}