asp.net core系统记录当前在线人数

实时记录当前在线人数，登录后保持120秒在线状态，在线状态保存在缓存中，采用滑动过期，在120秒内请求了系统，自动续活120秒；超过时间则移除用户在线状态；

• 需要在登录过滤器标记用户在线状态
• 需要排除循环请求的url，比如定时请求的待办数量
• 登录成功后标记用户在线

web记录当前在线人数状态

using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.Caching;
using System.Text;
using System.Threading.Tasks;namespace WuZiFenGongSiInfomation.Models
{/// <summary>/// 当前在线人数/// </summary>/// 2024-12-26 9:57:09， wanghaolipublic class OnlineUserAmount{static System.Collections.Concurrent.ConcurrentDictionary<string, bool> dict = new System.Collections.Concurrent.ConcurrentDictionary<string, bool>();/// <summary>/// 添加在线人/// </summary>/// <param name="userId">用户主键id</param>/// 2024-12-26 9:57:09， wanghaolipublic static void AddUserOnline(string userId){dict.TryAdd(userId, true);System.Runtime.Caching.MemoryCache.Default.AddOrGetExisting("AddUserOnline." + userId, 1, new CacheItemPolicy(){SlidingExpiration = TimeSpan.FromSeconds(120),RemovedCallback = (args) =>{string userId2 = args.CacheItem.Key;System.Diagnostics.Debug.WriteLine("移除用户在线状态 ，key=" + userId2);LogHelpter.AddLog("移除用户在线状态，key=" + userId2, null, "UserOnline");string userId3 = userId2.Replace("AddUserOnline.","");bool removeResult = dict.TryRemove(userId3, out bool k);if (removeResult){System.Diagnostics.Debug.WriteLine("移除用户在线状态成功，key=" + userId2);LogHelpter.AddLog("移除用户在线状态成功，key=" + userId2, null, "UserOnline");}}});}/// <summary>/// 标记用户在线，续活/// </summary>/// <param name="userId"></param>/// 2024-12-26 10:04:09，   wanghaolipublic static void VisitUseStatCache(string userId){string key = "AddUserOnline." + userId;bool exists = System.Runtime.Caching.MemoryCache.Default.Contains(key);if (exists){               }else{AddUserOnline(userId);}System.Diagnostics.Debug.WriteLine("激活用户在线状态，key=" + userId);LogHelpter.AddLog("激活用户在线状态，key=" + userId,null, "UserOnline");}/// <summary>/// 当前在线人数/// </summary>/// <returns></returns>public static int GetOnlineUserAmount(){return dict.Count;}}
}