How to visually indicate current page in ASP.NET MVC?

Question

As a base for discussion. Create a standard ASP.NET MVC Web project.

It will contain two menu items in the master page:

Answer 1

If you are using T4MVC, you can use this:

        public static HtmlString MenuLink(
        this HtmlHelper helper,
        string text,
        IT4MVCActionResult action,
        object htmlAttributes = null)
    {
        var currentController = helper.ViewContext.RouteData.Values["controller"] as string ?? "home";
        var currentAction = helper.ViewContext.RouteData.Values["action"] as string ?? "index";

        var attributes = new RouteValueDictionary(htmlAttributes);
        var cssClass = (attributes.ContainsKey("class"))
                           ? attributes["class"] + " "
                           : string.Empty;

        string selectedClass;
        if(action.Controller.Equals(currentController, StringComparison.InvariantCultureIgnoreCase)
        {
            selectedClass = "selected-parent";
            if(action.Action.Equals(currentAction, StringComparison.InvariantCultureIgnoreCase))
                selectedClass = "selected";
        }
        cssClass += selectedClass;

        attributes["class"] = cssClass;

        return helper.ActionLink(text, (ActionResult)action, attributes);
    }