web api操作筛选器没有调用，为什么？

// 定义筛选器
public class MyCustomFilter : IActionFilter
{
    public void OnActionExecuting(ActionExecutingContext filterContext)
    {
        Console.WriteLine("OnActionExecuting called");
    }

    public void OnActionExecuted(ActionExecutedContext filterContext)
    {
        Console.WriteLine("OnActionExecuted called");
    }
}

// 控制器
public class ValuesController : ApiController
{
    [HttpGet]
    [MyCustomFilter]
    public IHttpActionResult Get()
    {
        return Ok("Hello, World!");
    }
}

// 注册筛选器
public static class FilterConfig
{
    public static void RegisterGlobalFilters(HttpConfiguration config)
    {
        config.Filters.Add(new MyCustomFilter());
    }
}

// 在 Global.asax.cs 中调用注册方法
public class WebApiApplication : System.Web.HttpApplication
{
    protected void Application_Start()
    {
        GlobalConfiguration.Configure(WebApiConfig.Register);
        FilterConfig.RegisterGlobalFilters(GlobalConfiguration.Configuration.Filters);
    }
}