Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

JavaScript DOM Scripting By Example Adding and Removing Names RSVP Checkbox

Posted by trottly
trottly
5,394 Points

When changing the class name to "responded" ..

When changing an element's class name in JavaScript, does the browser then also check the CSS during the change to see if styling needs to be applied? I'm mostly curious about how the new styling is applied by only changing the class name.

1 Answer

Jonathan Grieve
MOD
Jonathan Grieve
Treehouse Moderator 91,252 Points
Jonathan Grieve
Jonathan Grieve
Treehouse Moderator 91,252 Points

Any change in the styling is governed by CSS specificity. So it'd look for the existence of a CSS class and style the element accordingly.

Changing the class doesn't change anything in the stylesheet, so you'd have to set up the markup and the CSS that style both "states" in your app before you write the JavaScript that changes the class attribute. :-)