How to Highlight navbar Menu Items in using TagHelpers (Asp.Net.MVC6 6.0.0-rc1.0-final)

Question

I want to generate class="active" in menu links in asp.net 5 1.0.0-rc1-final, to highlight the active menus of the navbar in _Layout.cshtml.
The solution proposed here: Original post by Prashant Adepu works fine in Asp.Net.MVC 6.0.0 beta5. However in 6.0.0 rc1 (asp.net 1.0.0 rc-1 final), it seems impossible to use [ViewContext] decoration since this attribute does not exist.
Is there a way around this?

1) Below is the code with minor adaptation to rc-1.
Everything works except for [ViewContext] which is rejected. Without this attribute, the viewContext will be null in runtime).
2) To run it you should create an asp.net5 WebApplicationX, and add @addTagHelper "WebApplicationX.TagHelpers.MenuLinkTagHelper, WebApplicationX" in _ViewImports.cshtml.
Then just use <menulink controller-name="Home" action-name="About" menu-text="About"></menulink> instead of a regular mvc <a asp-controller="Home" asp-action="Index">Home</a> Anchor.

using Microsoft.AspNet.Mvc;
using Microsoft.AspNet.Mvc.Rendering;
using Microsoft.AspNet.Razor.Runtime.TagHelpers;
using Microsoft.AspNet.Razor.TagHelpers;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace WebApplicationX.TagHelpers
{
    [HtmlTargetElement("menulink", Attributes = "controller-name, action-name, menu-text")]
    public class MenuLinkTagHelper : TagHelper 
    {
        public string ControllerName { get; set; }
        public string ActionName { get; set; }
        public string MenuText { get; set; }
        [ViewContext]                         //*** This is not allowed.***
        public ViewContext ViewContext { get; set; }

        public IUrlHelper _UrlHelper { get; set; }

        public MenuLinkTagHelper(IUrlHelper urlHelper)
        {
            _UrlHelper = urlHelper;
        }

        public override void Process(TagHelperContext context, TagHelperOutput output)
        {
            StringBuilder sb = new StringBuilder();

            string menuUrl = _UrlHelper.Action(ActionName, ControllerName);

            output.TagName = "li";

            var a = new TagBuilder("a");
            a.MergeAttribute("href", $"{menuUrl}");
            a.MergeAttribute("title", MenuText);
            a.InnerHtml.Append(MenuText);

            var routeData = ViewContext.RouteData.Values;
            var currentController = routeData["controller"];
            var currentAction = routeData["action"];

            if (String.Equals(ActionName, currentAction as string, StringComparison.OrdinalIgnoreCase)
                && String.Equals(ControllerName, currentController as string, StringComparison.OrdinalIgnoreCase))
            {
                output.Attributes.Add("class", "active");
            }

            output.Content.SetContent(a.ToString());
        }
    }
}

Answer 1

Thanks to Danny's help, and after revisiting the original, you can find below the working code for 1.0.0-rc1-final

    using Microsoft.AspNet.Mvc;
    using Microsoft.AspNet.Mvc.Rendering;
    using Microsoft.AspNet.Mvc.ViewFeatures;                    //change for 1.0.0-rc1.0-final
    using Microsoft.AspNet.Razor.TagHelpers;
    using System;
    using System.Text;

namespace WebAppName.TagHelpers
{
    [HtmlTargetElement("menulink", Attributes = "controller-name, action-name, menu-text")]
    public class MenuLinkTagHelper : TagHelper
    {
        public string ControllerName { get; set; }
        public string ActionName { get; set; }
        public string MenuText { get; set; }
        [ViewContext]
        public ViewContext ViewContext { get; set; }

        public IUrlHelper _UrlHelper { get; set; }

        public MenuLinkTagHelper(IUrlHelper urlHelper)
        {
            _UrlHelper = urlHelper;
        }

        public override void Process(TagHelperContext context, TagHelperOutput output)
        {
            StringBuilder sb = new StringBuilder();

            string menuUrl = _UrlHelper.Action(ActionName, ControllerName);

            output.TagName = "li";

            var a = new TagBuilder("a");
            a.MergeAttribute("href", $"{menuUrl}");
            a.MergeAttribute("title", MenuText);
            a.InnerHtml.Append(MenuText);                    //change for 1.0.0-rc1.0-final

            var routeData = ViewContext.RouteData.Values;
            var currentController = routeData["controller"];
            var currentAction = routeData["action"];

            if (String.Equals(ActionName, currentAction as string, StringComparison.OrdinalIgnoreCase)
                && String.Equals(ControllerName, currentController as string, StringComparison.OrdinalIgnoreCase))
            {
                output.Attributes.Add("class", "active");
            }
            output.Content.Append(a);                    //change for 1.0.0-rc1.0-final
        }
    }
}

Answer 2

ViewContext attribute is still there. It's in Microsoft.AspNet.Mvc.ViewFeatures, not in Microsoft.AspNet.Mvc.Rendering (where ViewContext class itself is). Make sure to pick the right one. You can check out an example here: https://github.com/DannyvanderKraan/TagHelpers