Identity 2.0默认项目缺少默认类

Question

根据几篇文章;我会注意到一个：

http://typecastexception.com/post/2014/04/20/ASPNET-MVC-and-Identity-20-Understanding-the-Basics.aspx#Application-User-Manager-and-Application-Role-Manager

，IdentityConfig.cs中应该有两个辅助类

1. ApplicationUserManager
2. ApplicationRoleManager

我现在已经谷歌搜索了一段时间，似乎无法弄清楚为什么我在默认的MVC 5网络应用中没有ApplicationRoleManager。我也遗漏了ApplicationUserManager中的方法，例如AddUserToRolesAsync和RemoveUserFromRolesAsync。我的IdentityConfig.cs文件中包含以下代码。

public class ApplicationUserManager : UserManager<ApplicationUser>
{
    public ApplicationUserManager(IUserStore<ApplicationUser> store)
        : base(store)
    {
    }

    public static ApplicationUserManager Create(IdentityFactoryOptions<ApplicationUserManager> options, IOwinContext context) 
    {
        var manager = new ApplicationUserManager(new UserStore<ApplicationUser>(context.Get<ApplicationDbContext>()));
        // Configure validation logic for usernames
        manager.UserValidator = new UserValidator<ApplicationUser>(manager)
        {
            AllowOnlyAlphanumericUserNames = false,
            RequireUniqueEmail = true
        };
        // Configure validation logic for passwords
        manager.PasswordValidator = new PasswordValidator
        {
            RequiredLength = 6,
            RequireNonLetterOrDigit = true,
            RequireDigit = true,
            RequireLowercase = true,
            RequireUppercase = true,
        };
        // Register two factor authentication providers. This application uses Phone and Emails as a step of receiving a code for verifying the user
        // You can write your own provider and plug in here.
        manager.RegisterTwoFactorProvider("PhoneCode", new PhoneNumberTokenProvider<ApplicationUser>
        {
            MessageFormat = "Your security code is: {0}"
        });
        manager.RegisterTwoFactorProvider("EmailCode", new EmailTokenProvider<ApplicationUser>
        {
            Subject = "Security Code",
            BodyFormat = "Your security code is: {0}"
        });
        manager.EmailService = new EmailService();
        manager.SmsService = new SmsService();
        var dataProtectionProvider = options.DataProtectionProvider;
        if (dataProtectionProvider != null)
        {
            manager.UserTokenProvider = new DataProtectorTokenProvider<ApplicationUser>(dataProtectionProvider.Create("ASP.NET Identity"));
        }
        return manager;
    }
}

public class EmailService : IIdentityMessageService
{
    public Task SendAsync(IdentityMessage message)
    {
        // Plug in your email service here to send an email.
        return Task.FromResult(0);
    }
}

public class SmsService : IIdentityMessageService
{
    public Task SendAsync(IdentityMessage message)
    {
        // Plug in your sms service here to send a text message.
        return Task.FromResult(0);
    }
}