telegram-bot/Core/Service/UserService.cs

using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.Extensions.Configuration;
using Telegram.Bot.Types;

namespace Kruzya.TelegramBot.Core.Service
{
    public class UserService
    {
        private List<long> _superUsers;
        
        public UserService(IConfiguration configuration)
        {
            _superUsers = configuration.GetSection("SuperUsers")
                .GetChildren()
                .Select(q => Convert.ToInt64(q.Value))
                .ToList();
        }

        public bool IsUserSuper(User user)
        {
            return IsUserSuper(user.Id);
        }
        
        public bool IsUserSuper(long userId)
        {
            return _superUsers.Contains(userId);
        }
    }
}