C# helper to return the controller name, action name, and a combination of the two (based on haml's page_class helper)

PageCssClass.cs

public static string PageCssClass(this HtmlHelper helper, string seperator="-")
{
    string names = String.Format("{0} {1} {0}{2}{1}", 
                        helper.ViewContext.RouteData.Values["Controller"], 
                        helper.ViewContext.RouteData.Values["Action"],
                        seperator);
    return names.ToLower();
}