使用Socket IO的WebSocket握手错误404

Question

我在客户端上使用React native，并在服务器上使用io套接字

这是我在服务器端的代码

io.on("connection", (socket) => {
  console.log("New connection joined");

  socket.on("disconnect", () => console.log("User disconnected"));
})

这是在客户端

 useEffect(() => {
    socket = io("http://localhost:5000", { transports: ['websocket'] });
  }, [])

并且错误不断 websocket.js:120 WebSocket connection to 'ws://localhost:5000/socket.io/?EIO=3&transport=websocket' failed: Error during WebSocket handshake: Unexpected response code: 404