Using Socket in Flutter apps?

Question

I create a Flutter App. I need to connect my app to local network socket services. As shown below, I can use telnet Connect, Send data and Receive data from the server. I us

Answer 1

As attdona mentioned,

Your server does not speak the websocket protocol but it exposes a plain tcp socket.

So you need a TCP socket and there is a great tutorial on Sockets and ServerSockets which you can find here.

Here's a snippet:

import 'dart:io';
import 'dart:async';

Socket socket;

void main() {
   Socket.connect("localhost", 4567).then((Socket sock) {
   socket = sock;
   socket.listen(dataHandler, 
      onError: errorHandler, 
      onDone: doneHandler, 
      cancelOnError: false);
   }).catchError((AsyncError e) {
      print("Unable to connect: $e");
   });
   //Connect standard in to the socket 
   stdin.listen((data) => socket.write(new String.fromCharCodes(data).trim() + '\n'));
}

void dataHandler(data){
   print(new String.fromCharCodes(data).trim());
}

void errorHandler(error, StackTrace trace){
   print(error);
}

void doneHandler(){
   socket.destroy();
}