Learning jQuery 3 - Fifth Edition

Consolidating code using event context

The code optimization we've just completed is an example of refactoring--modifying existing code to perform the same task in a more efficient or elegant way. To explore further refactoring opportunities, let's look at the behaviors we have bound to each button. The .removeClass() method's parameter is optional; when omitted, it removes all classes from the element. We can streamline our code a bit by exploiting this as follows:

$(() => {  $('#switcher-default')     .addClass('selected')     .on('click', () => {       $('body').removeClass();     });  $('#switcher-narrow')    .on('click', () => {       $('body')        .removeClass()        .addClass('narrow');     });   $('#switcher-large')    .on('click', () => {       $('body')        .removeClass() .addClass('large'); ...