unity Socket服务端

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using System.Net;           //IPAddress，IPEndPoint
using System.Net.Sockets;   //建立套接字socket
using System.Threading;     //建立线程thread
using System.Text;
using System.IO;
using System.Xml;

public class ServerSocketHandlers : MonoBehaviour
{

    // Start is called before the first frame update
    void Start()
    {
        openServer();
    }

    // Update is called once per frame
    void Update()
    {
        Send();
    }

    public void openServer()
    {
        try
        {
            IPAddress pAddress = IPAddress.Parse("127.0.0.1");        //IP
            IPEndPoint pEndPoint = new IPEndPoint(pAddress, 3001);    //端口号
            Socket socket_server = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            socket_server.Bind(pEndPoint);
            socket_server.Listen(5);//设置最大连接数
            Debug.Log("监听成功");
            //创建新线程执行监听，否则会阻塞UI，导致unity无响应
            Thread thread = new Thread(listen);
            thread.IsBackground = true;
            thread.Start(socket_server);
        }
        catch (System.Exception)
        {
            throw;
        }
    }

    Socket socketSend;

    public void Send()   //要写成public，button的onclick才能捕捉到
    {
        string danmustr = "{ \"type\": \"danmu\", \"UID\": 16125790, \"uname\": \"咕之助\", \"msg\": \"";

        byte[] buffer = Encoding.UTF8.GetBytes(danmustr);
        socketSend.Send(buffer);
    }

    void listen(object o)    //不管接受还是发送都要先监听
    {
        try
        {
            Socket socketWatch = o as Socket;
            while (true)
            {
                socketSend = socketWatch.Accept();
                Debug.Log(socketSend.RemoteEndPoint.ToString() + ":" + "连接成功");
                
                Thread r_thread = new Thread(Received);   //可以不要这个接受，只负责发送（发送可以写在update里）
                r_thread.IsBackground = true;
                r_thread.Start(socketSend);
                
            }
        }
        catch (System.Exception)
        {

            throw;
        }
    }
    
    void Received(object o)
    {
        try
        {
             Socket socketSend = o as Socket;
             while (true)
             {
                byte[] buffer = new byte[1024];
                int len = socketSend.Receive(buffer);
                if (len == 0) break;
                string str = Encoding.UTF8.GetString(buffer, 0, len);
                Debug.Log("服务器打印客户端返回消息：" + socketSend.RemoteEndPoint + ":" + str);
                
                Send();       //也可以跟在接受的消息后再发送
                
             }
         }
         catch (System.Exception)
        { 
             throw;
         }
     }

}