套接字IO-React应用无法连接到NodeJS服务器

Question

这是我的服务器端代码

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

io.on('connection', (socket) => {
  console.log('connected');
  socket.on('message', (msg) => {
    console.log(msg);
  });
});

const PORT = 3000;
server.listen(PORT, () => {
  console.log(`Server is running on port ${PORT}.`);
});

这是我的客户端 React Native组件

import React, {useEffect} from 'react';
import {View, Text} from 'react-native';

import clientio from 'socket.io-client';
const ENDPOINT = 'http://127.0.0.1:3000';

export default () => {
  useEffect(() => {
    const socket = clientio(ENDPOINT);
    console.log(socket.connected);
    socket.emit('message', {message: 'hello'});
  }, []);

  return (
    <View>
      <Text> Hello </Text>
    </View>
  );
};

useEffect中的console.log总是注销“ false” +我在服务器端没有任何日志。

尝试了不同的端口，将uri更改为“ http：// localhost：3000”

我正在使用软件包：

“ socket.io”：NodeJS应用中的“ 2.3.0”

“ socket.io-client”：“ 2.3.0”，在React应用中