btcpayserver/BTCPayServer/Views/Server/ServerNavPages.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc.Rendering;
using Microsoft.AspNetCore.Mvc.ViewFeatures;

namespace BTCPayServer.Views.Server
{
	public static class ServerNavPages
	{
		public static string ActivePageKey => "ActivePage";
		public static string Index => "Index";


		public static string Users => "Users";
		public static string Hangfire => "Hangfire";

		public static string UsersNavClass(ViewContext viewContext) => PageNavClass(viewContext, Users);
		public static string HangfireNavClass(ViewContext viewContext) => PageNavClass(viewContext, Hangfire);

		public static string IndexNavClass(ViewContext viewContext) => PageNavClass(viewContext, Index);

		public static string PageNavClass(ViewContext viewContext, string page)
		{
			var activePage = viewContext.ViewData["ActivePage"] as string;
			return string.Equals(activePage, page, StringComparison.OrdinalIgnoreCase) ? "active" : null;
		}

		public static void AddActivePage(this ViewDataDictionary viewData, string activePage) => viewData[ActivePageKey] = activePage;
	}
}