更新：在最近的测试版，从 ConfigureServices 配置安全选项是不不再可能（除了身份）。现在，您需要直接配置JWT选项时调用 app.UseJwtBearerAuthentication（）：

Update: in recent betas, configuring security options from ConfigureServices is no longer possible (except for Identity). You now need to directly configure the JWT options when calling app.UseJwtBearerAuthentication():

public void Configure(IApplicationBuilder app) {
    app.UseJwtBearerAuthentication(options => {
        // Configure the JWT options here.
    });
}

您忘了添加的OAuth2承载认证中间件在您的管道：

You forgot to add the OAuth2 bearer authentication middleware in your pipeline:

public void Configure(IApplicationBuilder app, IHostingEnvironment env) {
    app.UseStaticFiles();

    app.UseOAuthBearerAuthentication();

    app.UseIdentity();

    app.UseMvc(routes => {
        routes.MapRoute(
            name: "default",
            template: "api/{controller}/{action}/{id?}",
            defaults: new {
                controller = "Home",
                action = "Index"

            });
    });
}

你还没有使用推荐的方法来注册了的OAuth2承载中间件使用的设置：

You're also not using the recommended approach to register the settings used by the OAuth2 bearer middleware:

public void ConfigureServices(IServiceCollection services) {
    // Not recommended approach.
    services.AddInstance(new OAuthBearerAuthenticationOptions { });

    // Recommended approach.
    services.ConfigureOAuthBearerAuthentication(options => {
        // Configure the options used by the OAuth2 bearer middleware.
    });
}