index.js

var server_port = 65432;
var server_addr = "192.168.31.81";

function client(){
    const net = require('net');
    var input = document.getElementById("myName").value;

    const client = net.createConnection({port: server_port, host: server_addr}, () => {
        console.log('connected to server!');
        client.write(`${input}\r\n`);
    });

    client.on('data', (data) => {
        document.getElementById("greet_from_server").innerHTML = data;
        console.log(data.toString());
        client.end();
        client.destroy();   
    });

    client.on('end', () => {
        console.log('disconnected from server');
    });
}
function greeting(){
    var name = document.getElementById("myName").value;
    document.getElementById("greet").innerHTML = "Hello " + name + " !";

    // to_server(name);
    client();
}