WebAPI：控制器上没有找到任何操作＆＃39; MobileApp＆＃39;符合名称＆＃39; services＆＃39;

Question

我已配置以下

config.MapHttpAttributeRoutes();

config.Routes.MapHttpRoute(
    name: "DefaultApi",
    routeTemplate: "api/{controller}/{id}",
    defaults: new { id = RouteParameter.Optional }
);

config.Routes.MapHttpRoute(
    name: "DefaultApiWithAction",
    routeTemplate: "api/{controller}/{action}/{id}",
    defaults: new { id = RouteParameter.Optional }
);

并拥有以下网络API

public class MobileAppController : ApiController
{
    [HttpGet, Route("api/mobileapp/services")]
    public dynamic services()
    {
        return new { Abc = 123 };
    }   
}

调用http://localhost:123/api/mobileapp/services

时出错

控制器上没有找到任何操作＆＃39; MobileApp＆＃39;符合名称＆＃39; services＆＃39;

Answer 1

将操作的返回值更改为IActionResult