Listing users and groups from ActiveDirectory

ActiveDirectory.cs

using System;
using System.Collections.Generic;
using System.DirectoryServices.AccountManagement;
using System.Linq;

namespace AugustoPedraza.Utils
{
    public class ActiveDirectory
    {
        public static string Domain { get; set; }

        public static IEnumerable<string> GetAllUsers()
        {
            return GetObject<UserPrincipal>();
        }

        public static IEnumerable<string> GetAllGroups()
        {
            return GetObject<GroupPrincipal>();
        }

        private static IEnumerable<string> GetObject<T>() where T: Principal
        {
            var principalContext = new PrincipalContext(ContextType.Domain, Domain);

            var itemPrincipal = (T)Activator.CreateInstance(typeof(T), new object[] { principalContext });
            var searcher = new PrincipalSearcher(itemPrincipal);

            return searcher.FindAll().OfType<T>().Select(x => x.SamAccountName).OrderBy(x => x);
        }
    }
}