부트스트랩 탐색을 위해 ASP.NET MVC의 Html.ActionLink에 '활성' 클래스를 추가하는 방법은 무엇입니까?

<ul class="nav navbar-nav">
    <li class="active">@Html.ActionLink("Home", "Index", "Home")</li>
    <li>@Html.ActionLink("About", "About", "Home")</li>
    <li>@Html.ActionLink("Contact", "Contact", "Home")</li>
</ul>

public static string IsSelected(this IHtmlHelper htmlHelper, string controllers, string actions, string cssClass = "selected")
{
    string currentAction = htmlHelper.ViewContext.RouteData.Values["action"] as string;
    string currentController = htmlHelper.ViewContext.RouteData.Values["controller"] as string;

    IEnumerable<string> acceptedActions = (actions ?? currentAction).Split(',');
    IEnumerable<string> acceptedControllers = (controllers ?? currentController).Split(',');

    return acceptedActions.Contains(currentAction) && acceptedControllers.Contains(currentController) ?
        cssClass : String.Empty;
}

<li class="@Html.IsSelected(actions: "Home", controllers: "Default")">
    <a href="@Url.Action("Home", "Default")">Home</a>
</li>