public Socket (System.Net.Sockets.AddressFamily addressFamily, 
               System.Net.Sockets.SocketType socketType,
               System.Net.Sockets.ProtocolType protocolType);

using System;
using System.Collections.Generic;
using System.Text;
using System.Net.Sockets;
using System.Net;
using System.Threading;
 
namespace MyServer
{
    class Client
    {
        private Socket clientSocket;
        private Thread t;
        private byte[] data = new byte[1024];
        public Client(Socket s)
        {
            clientSocket = s;
            //啟動(dòng)一個(gè)線程接受數(shù)據(jù);
            t = new Thread(ReceiveMessage);
            t.Start();
 
        }
        private void ReceiveMessage()
        {
            while (true)
            {
                //判斷連接是否斷開
 
               
                    if (clientSocket.Poll(10, SelectMode.SelectRead))
                    {
                    clientSocket.Close();
                        break;//跳出循環(huán)
 
                    }
               
 
                int length = clientSocket.Receive(data);
                string message = Encoding.UTF8.GetString(data, 0, length);
                //接受到數(shù)據(jù)要分發(fā)到客戶端
                Console.WriteLine("收到：" + message);
                Program.BroadcastMessage(message);
            }
        }
        public void SendMessage(string message)
        {
            byte[] data = Encoding.UTF8.GetBytes(message);
            clientSocket.Send(data);
        }
        public bool Connected
        {
            get { return clientSocket.Connected; }
        }
    }
 
 
    class Program
    {
        //存儲(chǔ)每一個(gè)客戶端
        static List<Client> clientList = new List<Client>();
 
        /// <summary>
        /// 服務(wù)器廣播這個(gè)消息
        /// </summary>
        /// <param name="message"></param>
        public static void BroadcastMessage(string message)
        {
            var notConnectedList = new List<Client>();
 
            foreach (var client in clientList)
            {
                if (client.Connected)
                    client.SendMessage(message);
                else
                    notConnectedList.Add(client);
            }
            foreach (var item in notConnectedList)
            {
                clientList.Remove(item);
            }
        }
 
        static void Main(string[] args)
        {
 
 
            Socket tcpServer = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            //192.168.xx.xxx
            tcpServer.Bind(new IPEndPoint(IPAddress.Parse("192.168.xx.xxx"), 7788));
            tcpServer.Listen(100);
 
            Console.WriteLine("服務(wù)器啟動(dòng)成功");
 
            while (true)
            {
                Socket clientSocket = tcpServer.Accept();
                Console.WriteLine("有一個(gè)客戶端連過來了");
                Client client = new Client(clientSocket);//收發(fā)消息放到Client類中處理
                clientList.Add(client);
            }
 
 
        }
    }
}

using System.Collections;
using System.Collections.Generic;
using System.Net.Sockets;
using UnityEngine;
using System.Net;
using UnityEngine.UI;
using System.Text;
using System.Threading;
 
public class MyClient : MonoBehaviour
{
    public string ipaddress = "192.168.xx.xxx";
    public int port=7788;
 
    private Socket clientSocket;
 
    private Thread t;
 
    private byte[] data = new byte[1024];
    public InputField inputField;
    public Text chat;
    public InputField myName;
    public string message = "";
    void Start()
    {
        ConnectToServer();
    }
    private void Update()
    {
        if (message != null && message !="")
        {
            chat.text += "\n" + message;
            message = "";
        }
    }
    private void ConnectToServer()
    {
        clientSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
        //發(fā)起連接
        clientSocket.Connect(new IPEndPoint(IPAddress.Parse(ipaddress), port));
        //創(chuàng)建一個(gè)新的線程接受消息
        t = new Thread(ReceiveMessage);
        t.Start();
 
    }
   //循環(huán)接受消息
    void ReceiveMessage()
    {
 
        while (true)
        {
            if (clientSocket.Connected == false)
                break;
            int length = clientSocket.Receive(data);
 
            message = Encoding.UTF8.GetString(data, 0, length);
 
          //  chat.text += "\n" + message;
        }
      
    }
    void SendMessages(string message)
    {
        byte[] data = Encoding.UTF8.GetBytes(message);
        clientSocket.Send(data);
    }
 
    public void OnSendButtonClick()
    {
        string value = myName.text+":"+ inputField.text;
        SendMessages(value);
        inputField.text = "";
    }
 
    private void OnDestroy()
    {
        t.Abort();
        clientSocket.Shutdown(SocketShutdown.Both);//既不接受也不發(fā)送
        clientSocket.Close();//關(guān)閉連接
    }
}