Advanced Node.js Development

Adding a newEmail custom event

Now, in order to listen to a custom event, we are still going to use socket.on; although, instead of specifying the name of one of the built-in events, we'll provide the first argument inside quotes as the name of our custom event. In this case, that name is going to be newEmail:

socket.on('newEmail');

Now, the second argument for socket.on is the same as the second argument for the built-in event listeners. We'll provide a function, and this function is going to get called when the event fires:

socket.on('newEmail', function () {});

For now, all we're going to do inside the function is use console.log to print a little message, New email:

socket.on('newEmail', function () {  console.log('New email');});

This ...