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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 91,253 Points
Jonathan Grieve
Jonathan Grieve
Treehouse Moderator 91,253 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. :-)