Asp.net 无法使用ApicController进行Owin身份验证质询

我无法获取

HttpContext.Current.GetOwinContext（）.Authentication.Challenge

来扩展

ApiController

它只是没有做任何事情，甚至没有错误。我只得到输出“：”

我做错了什么？这甚至可以实现吗？这是一个Web API，

控制器

注册表导致我的自定义路由出现问题

扩展

Controller

    public class AccountController : Controller
    {
        public void SignIn()
        {
            // Send an OpenID Connect sign-in request.
            if (!Request.IsAuthenticated)
            {
                HttpContext.GetOwinContext().Authentication.Challenge(new AuthenticationProperties { RedirectUri = "/" }, OpenIdConnectAuthenticationDefaults.AuthenticationType);
            }
        }
    }

扩展

ApiController

    [RoutePrefix("api/auth")]
    public class AuthController : ApiController
    {
        [HttpGet, Route("signin")]
        public IHttpActionResult SignIn()
        {
            if (User == null || User.Identity.IsAuthenticated == false)
            {
                HttpContext.Current.GetOwinContext().Authentication
                    .Challenge(new AuthenticationProperties() {RedirectUri = "/"}, OpenIdConnectAuthenticationDefaults.AuthenticationType);

                return Ok(":(");
            }

            return Ok(":)");
        }
    }

这不允许我的

ApiController

路由工作

        public static void RegisterRoutes(RouteCollection routes)
        {
            routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

            routes.MapRoute(
                name: "Default",
                url: "{controller}/{action}/{id}",
                defaults: new {controller = "Home", action = "Index", id = UrlParameter.Optional}
            );
        }