FrienDev/BusinessRules/OnlineRules.cs

using System.Collections.Generic;
using System.Web;
using FrienDev.Data;

namespace FrienDev.BusinessRules
{
    public class OnlineRules
    {
        public static OnlineRules Instance = new OnlineRules();

        private FrienDevDataContext m_DataContext = FrienDevDataContext.Instance;

        /// <summary>
        /// 在线用户的UserId集合，使用效率最高的HashSet<>
        /// </summary>