React native 如何使用socket.io列出react本机聊天应用程序中的所有用户？

我正在用React Native构建聊天应用程序。我想列出所有连接的用户，但我就是不能。 如何显示所有用户？ 谢谢

服务器端

 const app = require('express')();
 const server = require('http').Server(app);
 const io = require('socket.io')(server);

 const users= [];


 io.on("connection", function (socket) {
console.log("User connected", socket.id);

// attach incoming listener for new user
socket.on("user_connected", function (username) {
    // save in array
    users[usernames] = socket.id;

    // socket ID will be used to send message to individual person

    // notify all connected clients
    io.emit("user_connected", usernames);
});
});

server.listen(3001 ,() => console.log("Server Running on Port 3001"));

这是我的客户

componentDidMount(){
   const sender = this.state.username;

   console.log(sender);
 
   this.socket = io("http://192.168.1.102:3001");

   this.socket.emit("User_Connected",sender);

   this.socket.on("user_connected ", (username) => {

  
   })

  }