How can I send message to a specificate client?

[philwu]

Let's see, I already had a running websocket server. How can I take the initiative to send a message to one of them?

Currently, I can only:

Wait a message from a client and make response, or
Make a broadcast so every client can receive the message.
But what I want is sending to a client its own message by some logic.

Anyone help, please.

[GholibjonMadiyarov]

`server = new WebSocketServer(IPAddress.Any, 8000, true);
server.SslConfiguration.ServerCertificate = new X509Certificate2("file", "password");
server.SslConfiguration.EnabledSslProtocols = System.Security.Authentication.SslProtocols.Default | System.Security.Authentication.SslProtocols.Tls11 | System.Security.Authentication.SslProtocols.Tls12;

server.AddWebSocketService("/Web");
server.AddWebSocketService("/Desktop");
server.AddWebSocketService("/Mobile");

server.Log.File = AppDomain.CurrentDomain.BaseDirectory + "/ServerLog.txt";
server.KeepClean = false;

server.Start();

//Client id from db or file
string clientId = "9b0d327304bc433cb2c1968720cd2792";

//Message data
string message = "Hi!";

if (server.WebSocketServices["/Desktop"].Sessions.TryGetSession(clientId, out IWebSocketSession session))
{
//Client is open
if (session.State == WebSocketSharp.WebSocketState.Open)
{
server.WebSocketServices["/Desktop"].Sessions.SendTo(message, clientId);
//session.Context.WebSocket.Send(message);
}
}`

[lvqibin123]

wssv.WebSocketServices["/game"].Sessions.Broadcast
You access it like this.

[GholibjonMadiyarov]

This example is for sending messages to an individual client

[GholibjonMadiyarov]

your example to send message to all clients connected to module "/game"

[lvqibin123]

WriteException.cs
Used for writing logs!

using System;
using System.Collections.Generic;
using System.Text;
using System.IO;

namespace Helper
{
   
    public class WriteException
    {
        #region 单例懒加载
        private static readonly Lazy<WriteException> lazy = new Lazy<WriteException>(() => new WriteException());
        public static WriteException Instance { get { return lazy.Value; } }
        #endregion

        public void WriteBlog(string strTile, string strContent)
        {
            try
            {
                StreamWriter writer = File.AppendText(AppDomain.CurrentDomain.BaseDirectory + "Blog.dll");
                writer.WriteLine("-------------------------------------------");
                writer.WriteLine(strTile);
                writer.WriteLine(DateTime.Now.ToString());
                writer.WriteLine(strContent);
                writer.WriteLine("-------------------------------------------");
                writer.Flush();
                writer.Close();
            }
            catch (Exception)
            {
            }
        }

        /// <summary>
        /// 写入日志
        /// </summary>
        /// <param name="message"></param>
        public  string WriteLog(string strTile, string strContent)
        {
            string result = "";
            try
            {
                string path = AppDomain.CurrentDomain.BaseDirectory;
                path += "\\" + DateTime.Now.ToString("yyyy") + "\\" + DateTime.Now.ToString("MM") + "\\" + DateTime.Now.ToString("dd");
                if (!Directory.Exists(path))
                {
                    Directory.CreateDirectory(path);
                }
                string name = "czgl.log";

                DateTime dt = DateTime.Now;
                result = dt.ToString() + ":[" + strTile + "]" + strContent;

                StreamWriter writer = File.AppendText(path + "\\" + name);
                writer.WriteLine(result);
                writer.Flush();
                writer.Close();

                result = "[" + strTile + "]" + strContent + "   " + dt.ToString("yyyy-MM-dd HH:mm:ss ");
            }
            catch (Exception ex)
            {
                result = ex.Message;
            }
            return result;
        }

        /// <summary>
        /// 保存图片
        /// </summary>
        /// <param name="path"></param>
        /// <param name="data"></param>
        public void WriteImg(string path, ref byte[] data)
        {
            FileStream aFile = new FileStream(path, FileMode.Create);
            aFile.Seek(0, SeekOrigin.Begin);
            aFile.Write(data, 0, data.Length);
            aFile.Close();
        }


   
    }
}

CacheUtil.cs
Used for caching user information into file caching tool class!

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Runtime.Serialization.Formatters.Binary;
using System.Threading;

namespace Helper
{
    /// <summary>
    /// 缓存工具类
    /// </summary>
    public static class CacheUtil
    {
        #region 变量
        /// <summary>
        /// 缓存路径
        /// </summary>
        private static string folderPath = Application.StartupPath + "\\cache";
        /// <summary>
        /// 锁
        /// </summary>
        private static object _lock = new object();
        private static BinaryFormatter formatter = new BinaryFormatter();
        #endregion

        #region 构造函数
        static CacheUtil()
        {
            if (!Directory.Exists(folderPath))
            {
                Directory.CreateDirectory(folderPath);
            }
        }
        #endregion

        #region SetValue 保存键值对
        /// <summary>
        /// 保存键值对
        /// </summary>
        public static void SetValue(string key, object value, int expirationMinutes = 0)
        {
            CacheData data = new CacheData(key, value);
            data.updateTime = DateTime.Now;
            data.expirationMinutes = expirationMinutes;

            string keyMd5 = GetMD5(key);
            string path = folderPath + "\\" + keyMd5 + ".txt";
            lock (_lock)
            {
                using (FileStream fs = new FileStream(path, FileMode.OpenOrCreate, FileAccess.Write))
                {
                    fs.SetLength(0);
                    formatter.Serialize(fs, data);
                    fs.Close();
                }
            }
        }
        #endregion

        #region GetValue 获取键值对
        /// <summary>
        /// 获取键值对
        /// </summary>
        public static object GetValue(string key)
        {
            string keyMd5 = GetMD5(key);
            string path = folderPath + "\\" + keyMd5 + ".txt";
            if (File.Exists(path))
            {
                using (FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read))
                {
                    Console.WriteLine(" folderPath = {0}", folderPath);
                    Console.WriteLine(" path = {0}", path);
                    CacheData data = (CacheData)formatter.Deserialize(fs);
                    fs.Close();
                    if (data.expirationMinutes > 0 && DateTime.Now.Subtract(data.updateTime).TotalMinutes > data.expirationMinutes)
                    {
                        File.Delete(path);
                        return null;
                    }
                    return data.value;
                }
            }
            return null;
        }
        #endregion

        #region Delete 删除
        /// <summary>
        /// 删除
        /// </summary>
        public static void Delete(string key)
        {
            string keyMd5 = GetMD5(key);
            string path = folderPath + "\\" + keyMd5 + ".txt";
            if (File.Exists(path))
            {
                lock (_lock)
                {
                    File.Delete(path);
                }
            }
        }
        #endregion

        #region DeleteAll 全部删除
        /// <summary>
        /// 全部删除
        /// </summary>
        public static void DeleteAll()
        {
            string[] files = Directory.GetFiles(folderPath);
            foreach (string file in files)
            {
                File.Delete(file);
            }
        }
        #endregion

        #region 计算MD5值
        /// <summary>
        /// 计算MD5值
        /// </summary>
        private static string GetMD5(string value)
        {
            string base64 = Convert.ToBase64String(ASCIIEncoding.ASCII.GetBytes(value)).Replace("/", "-");
            if (base64.Length > 200)
            {
                MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();
                byte[] bArr = md5.ComputeHash(ASCIIEncoding.ASCII.GetBytes(value));
                StringBuilder sb = new StringBuilder();
                foreach (byte b in bArr)
                {
                    sb.Append(b.ToString("x2"));
                }
                return sb.ToString();
            }
            return base64;
        }
        #endregion
    }

    #region CacheData 缓存数据
    /// <summary>
    /// 缓存数据
    /// </summary>
    [Serializable]
    public class CacheData
    {
        /// <summary>
        /// 键
        /// </summary>
        public string key { get; set; }
        /// <summary>
        /// 值
        /// </summary>
        public object value { get; set; }
        /// <summary>
        /// 缓存更新时间
        /// </summary>
        public DateTime updateTime { get; set; }
        /// <summary>
        /// 过期时间(分钟)，0表示永不过期
        /// </summary>
        public int expirationMinutes { get; set; }

        public CacheData(string key, object value)
        {
            this.key = key;
            this.value = value;
        }
    }
    #endregion

}

Chat.cs
Used to receive data from the front-end! Store the name and session ID passed by the frontend in the OnOpen method and save them to a file!

using Helper;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
using System;
using System.Collections.Generic;
using System.Threading;
using WebSocketSharp;
using WebSocketSharp.Server;

namespace HKHTTP
{
  public class Chat : WebSocketBehavior
  {
    private string     _name;
    private static int _number = 0;
    private string     _prefix;
    /// 锁
    /// </summary>
    private static object _lock = new object();

    public Chat ()
    {
      _prefix = "sinovine#";
    }

    public string Prefix {
      get {
        return _prefix;
      }

      set {
        _prefix = !value.IsNullOrEmpty () ? value : "sinovine#";
      }
    }

    private string getName ()
    {
      WriteException.Instance.WriteLog("Chat ", "getName");
      var name = QueryString["name"];
      WriteException.Instance.WriteLog("Chat name = ", name);
      return !name.IsNullOrEmpty () ? name : _prefix + getNumber ();
    }

    private static int getNumber ()
    {
      return Interlocked.Increment (ref _number);
    }

    protected override void OnClose (CloseEventArgs e)
    {
        WriteException.Instance.WriteLog("Chat ", "OnClose");
      if (_name == null)
        return;

      var fmt = "{0} got logged off...";
      var msg = String.Format (fmt, _name);
      WriteException.Instance.WriteLog("Chat OnClose fmt = ", fmt);
      WriteException.Instance.WriteLog("Chat OnClose msg = ", msg);
      Sessions.Broadcast (msg);
    }

    protected override void OnMessage (MessageEventArgs e)
    {
        WriteException.Instance.WriteLog("Chat ", "OnMessage");
      var fmt = "{0}: {1}";
      var msg = String.Format (fmt, _name, e.Data);
      WriteException.Instance.WriteLog("Chat OnOpen ID = ", ID);
      WriteException.Instance.WriteLog("Chat OnMessage fmt = ", fmt);
      WriteException.Instance.WriteLog("Chat OnMessage msg = ", msg);
      Sessions.Broadcast(msg);
      //if (_name == "admin")
      //{
      //    Sessions.SendToAsync(e.Data, ID, (bool b) =>
      //    {
      //        WriteException.Instance.WriteLog("WebSocket SendToAsync b= ", b.ToString());
      //    });
      //}
    }

    protected override void OnOpen ()
    {
        WriteException.Instance.WriteLog("Chat ", "OnOpen");
      _name = getName ();

      var fmt = "{0} has logged in!";
      var msg = String.Format (fmt, _name);
      //foreach (WebSocketSessionManager sessions in Sessions.Sessions)
      //{
      //    sessions.
      //}
      lock (_lock)
      {
          string webSocketUserString = CacheUtil.GetValue("webSocketUserString").ToString();
          try
          {
              WriteException.Instance.WriteLog("Chat OnOpen webSocketUserString = ", webSocketUserString);
              if (webSocketUserString != "")
              {
                  WriteException.Instance.WriteLog("Chat OnOpen newDataString 不为空 newDataString = ", "");
                  JArray data = JsonConvert.DeserializeObject<JArray>(webSocketUserString);
                  WriteException.Instance.WriteLog("Chat OnOpen data = ", JsonConvert.SerializeObject(data, Formatting.Indented));
                  JArray newData = new JArray();
                  foreach (JObject d in data)
                  {
                      string name = d["name"].ToString();
                      string id = d["id"].ToString();
                      WriteException.Instance.WriteLog("Chat OnOpen newDataString 不为空 data name = ", name);
                      WriteException.Instance.WriteLog("Chat OnOpen newDataString 不为空 data id = ", id);
                      newData.Add(d);
                      //if (name != _name)
                      //{
                      //    newData.Add(d);
                      //}
                      //else
                      //{
                      //    IEnumerable<string> activeIDs = Sessions.ActiveIDs;
                      //    foreach (string sessionId in activeIDs)
                      //    {
                      //        WriteException.Instance.WriteLog("Chat OnOpen newDataString 不为空 sessions sessionId = ", sessionId);
                      //        if (sessionId != ID)
                      //        {
                      //            IWebSocketSession session;
                      //            Sessions.TryGetSession(sessionId, out session);
                      //            session.WebSocket.Close();
                      //            WriteException.Instance.WriteLog("Chat OnOpen newDataString 不为空 sessions sessionId = ", sessionId + "session Close!");
                      //        }
                      //    }
                      //}
                  }
                  JObject newSion = new JObject();
                  newSion["name"] = _name;
                  newSion["id"] = ID;
                  newData.Add(newSion);
                  string newDataString = JsonConvert.SerializeObject(newData, Formatting.Indented);
                  WriteException.Instance.WriteLog("Chat OnOpen newDataString 不为空 newDataString = ", newDataString);
                  CacheUtil.SetValue("webSocketUserString", newDataString);
              }
              else
              {
                  WriteException.Instance.WriteLog("Chat OnOpen 获取缓存  webSocketUserString  为空 ", "");
                  //string data = "{{\"name\":\"" + _name + "\",\"id\":\"" + ID + "\"}}";
                  JArray newData = new JArray();
                  JObject newSion = new JObject();
                  newSion["name"] = _name;
                  newSion["id"] = ID;
                  newData.Add(newSion);
                  string newDataString = JsonConvert.SerializeObject(newData, Formatting.Indented);
                  WriteException.Instance.WriteLog("Chat OnOpen 获取缓存  webSocketUserString  为空 newDataString = ", newDataString);
                  CacheUtil.SetValue("webSocketUserString", newDataString);

              }
          }
          catch (Exception ex)
          {
              WriteException.Instance.WriteLog("Chat OnOpen  ex= ", ex.StackTrace);
          }
      }
      WriteException.Instance.WriteLog("Chat OnOpen ID = ", ID);
      WriteException.Instance.WriteLog("Chat OnOpen fmt = ", fmt);
      WriteException.Instance.WriteLog("Chat OnOpen msg = ", msg);
      Sessions.Broadcast (msg);
       
    }
  }
}

How to use it?

private HttpServer wssv = new HttpServer(4649);
WriteException.Instance.WriteLog("WebSocket", "启动");
wssv.AddWebSocketService<Chat>("/Chat");
wssv.Start();
WriteException.Instance.WriteLog("WebSocket", "测试WebSocket发送信息");
            wssv.WebSocketServices["/Chat"].Sessions.Broadcast("成功了，呵呵！");
            string data = "{\"ch\":\"云D6H311\",\"jpgname\":\"192.168.22.9_20241204133632696\",\"ipaddr\":\"192.168.22.9\",\"type\":\"过磅未完成\"}";
            // 将JSON字符串反序列化为C#对象
            //wssv.WebSocketServices["/Chat"].Sessions.Broadcast(data);
          try
          {
              string webSocketUserString = CacheUtil.GetValue("webSocketUserString").ToString();
              WriteException.Instance.WriteLog("测试WebSocket发送信息 = ", webSocketUserString);
              if (webSocketUserString != "")
              {
                  WriteException.Instance.WriteLog("测试WebSocket发送信息  webSocketUserString 不为空 ", "");
                  JArray webSocketUser = JsonConvert.DeserializeObject<JArray>(webSocketUserString);
                  WriteException.Instance.WriteLog("测试WebSocket发送信息 webSocketUserString 不为空 data = ", JsonConvert.SerializeObject(webSocketUser, Formatting.Indented));
                  foreach (JObject d in webSocketUser)
                  {
                      string name = d["name"].ToString();
                      string id = d["id"].ToString();
                      IEnumerable<string> activeIDs = wssv.WebSocketServices["/Chat"].Sessions.ActiveIDs;
                      foreach (string sessionId in activeIDs)
                      {
                          WriteException.Instance.WriteLog("测试WebSocket发送信息 webSocketUserString 不为空 sessions sessionId = ", sessionId);
                          if(name=="admin"){
                               if (sessionId == id)
                              {
                                  IWebSocketSession session;
                                  wssv.WebSocketServices["/Chat"].Sessions.SendTo(data,id);
                                  WriteException.Instance.WriteLog("测试WebSocket发送信息 webSocketUserString 不为空 sessions sessionId = ", sessionId + "发送消息");
                              }
                          }
                      }
                  }
              }
              else
              {
                  WriteException.Instance.WriteLog("测试WebSocket发送信息  webSocketUserString 为空 ", "");
              }
            }
            catch (Exception ex)
            {
                WriteException.Instance.WriteLog("测试WebSocket发送信息  ex= ", ex.StackTrace);
          }

Front end request address!

"ws://192.168.3.100:4649/Chat?name="+usId

[lvqibin123]

Add a timer component to clear the task of closing WebSocket.

 private async void cleanWebSocketClosetimer_Tick(object sender, EventArgs e)
        {
            WriteException.Instance.WriteLog("定时清除关闭WebSocket的任务   ", "》》》》》》》》》》》》》》》》》");
            try
            {
                bool k =  wssv.WebSocketServices["/Chat"].Sessions.KeepClean;
                if (k) { 
                    string webSocketUserString = CacheUtil.GetValue("webSocketUserString").ToString();
                    WriteException.Instance.WriteLog("定时清除关闭WebSocket的任务 = ", webSocketUserString);
                    if (webSocketUserString != "")
                    {
                        JArray newData = new JArray();
                        WriteException.Instance.WriteLog("定时清除关闭WebSocket的任务  webSocketUserString 不为空 ", "");
                        JArray webSocketUser = JsonConvert.DeserializeObject<JArray>(webSocketUserString);
                        WriteException.Instance.WriteLog("定时清除关闭WebSocket的任务 webSocketUserString 不为空 data = ", JsonConvert.SerializeObject(webSocketUser, Formatting.Indented));
                        foreach (JObject d in webSocketUser)
                        {
                            string name = d["name"].ToString();
                            string id = d["id"].ToString();
                            IEnumerable<string> activeIDs = wssv.WebSocketServices["/Chat"].Sessions.ActiveIDs;
                            foreach (string sessionId in activeIDs)
                            {
                                if (sessionId == id)
                                {
                                    newData.Add(d);
                                }
                            }
                        }
                        string newDataString = JsonConvert.SerializeObject(newData, Formatting.Indented);
                        WriteException.Instance.WriteLog("定时清除关闭WebSocket的任务 不为空 newDataString = ", newDataString);
                        CacheUtil.SetValue("webSocketUserString", newDataString);
                    }
                    else
                    {
                        WriteException.Instance.WriteLog("定时清除关闭WebSocket的任务  webSocketUserString 为空 ", "");
                    }
                }
            }
            catch (Exception ex)
            {
                WriteException.Instance.WriteLog("定时清除关闭WebSocket的任务  ex= ", ex.StackTrace);
            }
            WriteException.Instance.WriteLog("定时清除关闭WebSocket的任务   ", "》》》》》》》》》》》》》》》》》");

        }

[GholibjonMadiyarov]

Hi

[GholibjonMadiyarov]

1. Why do you use HttpServer and not WebSocket() if you want to develop Chat?

[GholibjonMadiyarov]

I will try to prepare for you a scheme for the implementation of the Chat!

[lvqibin123]

The case I saw, WebSocket (), is used to send messages to clients, while HttpServer receives messages sent by clients. I only thought of this way to handle it!

[lvqibin123]

This plan can meet my current needs.

[GholibjonMadiyarov]

But I prefer to use only socket for both sides

[GholibjonMadiyarov]

Client:

[GholibjonMadiyarov]

var client = new WebSocket(ApplicationConfigurations.getConfig("websocket_host"));

client.SslConfiguration.ServerCertificateValidationCallback =
(s, certificate, chain, sslPolicyErrors) =>
{
// Do something to validate the server certificate.
return true; // If the server certificate is valid.
};

client.OnOpen += Client_OnOpen;
client.OnMessage += Client_OnMessage;
client.OnClose += Client_OnClose;
client.OnError += Client_OnError;

client.Compression = CompressionMethod.Deflate;

client.Log.File = AppDomain.CurrentDomain.BaseDirectory + "/WebSocketLog.txt";

client.Connect();

// Events
private void Client_OnOpen(object sender, EventArgs e)
{
Log.toFile("OpenLog.txt", "[Open]);
}

private void Client_OnMessage(object sender, MessageEventArgs e)
{
Log.toFile("MessageLog.txt", "[Message] Data:" + e.Data);
}

private void Client_OnClose(object sender, CloseEventArgs e)
{
Log.toFile("CloseLog.txt", "[Close] Code: " + e.Code + ", Reason:" + e.Reason + ", WasClean:" + e.WasClean);
}

private void Client_OnError(object sender, WebSocketSharp.ErrorEventArgs e)
{
Log.toFile("ErrorLog.txt", "[Error] Message:" + e.Message);
}

[GholibjonMadiyarov]

Server (Better implementation in Windows service):