Advanced Node.js Development

Moving the JavaScript into a separate file

As you might have noticed in the last section, I accidentally used ES6 arrow functions inside our client-side JavaScript code. As I mentioned, we want to avoid this; the project is going to work correctly in Chrome, but if you tried to load it up on your mobile phone, Internet Explorer, Safari, or some versions of Firefox, the program would crash. So, instead of using arrow functions, we'll use regular functions by removing the arrow and adding the function keyword before our arguments. I'll do this for the on('connect' listener and for the on('disconnect' listener, adding the function keyword and removing the arrow:

socket.on('connect', function () {  console.log('Connected to server');});socket.on('disconnect', ...