问IServiceCollection不包含AddDefaultIdentity的定义

EN

public class Program
{
    public async static void Main(string[] args)
    {
        await Host.CreateDefaultBuilder(args)
        .ConfigureWebHostDefaults(webBuilder => {
           webBuilder.UseContentRoot(Directory.GetCurrentDirectory());
           webBuilder.UseKestrel();
           webBuilder.UseAzureAppServices();
           webBuilder.UseStartup<Startup>();
       })
      .Build()
      .RunAsync();
   }
}

public class Startup
{
    public Startup(IConfiguration configuration, IHostEnvironment hostEnvironment)
    {
        Configuration = configuration;
        HostEnvironment = hostEnvironment;
    }

    public IConfiguration Configuration { get; }
    protected IApplicationBuilder ApplicationBuilder { get; private set; }
    public IHostEnvironment HostEnvironment { get; }

    // This method gets called by the runtime. Use this method to add services to the container.
    public void ConfigureServices(IServiceCollection services)
    {
        //           services.AddRazorPages();

        services.AddDefaultIdentity<ApplicationUser>()  // "ApplicationUser" is named incorrectly, it should be "IdentityUser" instead, as per Microsoft documentation.
            .AddRoles<IdentityRole<Guid>>()
            .AddEntityFrameworkStores<ApplicationContext, Guid>()  // FYI - AddEntityFrameworkStores() deal with role that derives from IdentityRole, as per documentation.
            //.AddDefaultUI()
            .AddDefaultTokenProviders();

        // [ Old version #1 - replacement ]
        services.ConfigureApplicationCookie(options =>
        {
            options.LoginPath = new PathString("/Home/Index");
            options.SlidingExpiration = true;
            options.ExpireTimeSpan = TimeSpan.FromMinutes(this.Configuration.GetValue<int?>("Authentication:SlidingExpirationTime").Value);
            options.AccessDeniedPath = new PathString("/Home/AccessDenied");
        });

        // [ Old version #2 - replacement ]
        services.Configure<IdentityOptions>(options =>
        {
            options.Password.RequireUppercase = false;
            options.Password.RequireLowercase = false;
            options.Password.RequireNonAlphanumeric = false;
            options.Password.RequireDigit = false;
            options.Password.RequiredLength = 7;
        });

        services.AddMvc();
        services.AddSession();

        //services.Configure<AuthorizationOptions>(options =>
        //{
        //});
    }

    // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        if (env.IsDevelopment())
        {
           app.UseDeveloperExceptionPage();
        }
        else
        {
            app.UseExceptionHandler("/Error");
        }

        app.UseHttpsRedirection();
        app.UseStaticFiles();
        app.UseRouting();
        app.UseAuthorization();
        app.UseEndpoints(endpoints =>
        {
            endpoints.MapRazorPages();
        });

        // Config Exception.
        if (env.IsDevelopment())
            app.UseDeveloperExceptionPage();
        else
            app.UseExceptionHandler("/Home/ErrorPage.html");
        
        app.UseStaticFiles(); // Note, we are not authenticating for static files if this is before them
        app.UseSession();
        app.UseAuthentication();

        // MVC.
        // app.UseMvc(routes => routes.MapRoute("default", "{controller=Home}/{action=Index}/{id?}"));
    }
}

public class ApplicationUser : IdentityUser<Guid>, IUser
{
}

public interface IUser
{
}

public class ApplicationContext : IdentityDbContext<ApplicationUser, IdentityRole<Guid>, Guid>
{
    public ApplicationContext(DbContextOptions<ApplicationContext> options)
        : base(options)
    {
    }

    protected override void OnModelCreating(ModelBuilder builder)
    {
        base.OnModelCreating(builder);
    }
}

<Project Sdk="Microsoft.NET.Sdk.Web">
  <PropertyGroup>
    <TargetFramework>netcoreapp3.1</TargetFramework>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.ApplicationInsights.AspNetCore" Version="2.0.0" />
    <PackageReference Include="Microsoft.AspNetCore.DataProtection" Version="3.1.3" />
    <PackageReference Include="Microsoft.AspNetCore.DataProtection.AzureStorage" Version="1.0.2" />
    <PackageReference Include="Microsoft.AspNetCore.Diagnostics" Version="1.1.2" />
    <PackageReference Include="Microsoft.AspNetCore.Mvc.Formatters.Xml" Version="1.1.3" />
    <PackageReference Include="Microsoft.AspNetCore.Session" Version="1.1.2" />
    <PackageReference Include="Microsoft.AspNetCore.StaticFiles" Version="1.1.2" />
    <PackageReference Include="Microsoft.Extensions.Configuration.Binder" Version="3.1.3" />
    <PackageReference Include="Microsoft.Extensions.Configuration.CommandLine" Version="3.1.3" />
    <PackgaeReference Include="Microsoft.Extensions.Hosting" Version="3.1.3" />
    <PackageReference Include="Microsoft.Extensions.Logging.Console" Version="3.1.3" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="3.1.3" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.InMemory" Version="3.1.3" />
    <PackageReference Include="Microsoft.AspNetCore.Identity" Version="2.2.0" />
    <PackageReference Include="Microsoft.AspNetCore.Identity.EntityFrameworkCore" Version="3.1.3" />
    <PackageReference Include="Microsoft.AspNetCore.Mvc" Version="1.1.3" />
    <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="3.1.3" />
    <PackageReference Include="Microsoft.AspNetCore.Mvc" Version="1.1.3" />
    <PackageReference Include="Microsoft.AspNetCore.Mvc.Formatters.Json" Version="1.1.3" />
    <PackageReference Include="Microsoft.AspNetCore.Server.IISIntegration" Version="1.1.2" />
    <PackageReference Include="Microsoft.AspNetCore.Server.Kestrel" Version="1.1.2" />
    <PackageReference Include="Microsoft.AspNetCore.StaticFiles" Version="1.1.2" />
    <PackageReference Include="Newtonsoft.Json" Version="12.0.2" />
    <PackageReference Include="Microsoft.AspNetCore.AzureAppServicesIntegration" Version="1.0.2" />
  </ItemGroup>
</Project>

services.AddDefaultIdentity<ApplicationUser>() 
.AddRoles<IdentityRole<Guid>>()
.AddEntityFrameworkStores<ApplicationContext, Guid>() 
.AddDefaultTokenProviders();