Tips for accessing a DOM element's ::before content using JavaScript

Is there a way to retrieve the content of a DOM element's ::before pseudo-element that was applied using CSS3?

I've attempted several methods without success, and I'm feeling very confused!

// https://rollbar.com/docs/

const links = document.querySelectorAll(`ul.image-list a`);

links[0];
// <a href="/docs/notifier/rollbar-gem/" class="ruby">::before Ruby</a>

links[0];
//

links[0].textContent;
//"Ruby"

links[0].innerText;
// "Ruby"

links[0].innerHTML;
// "Ruby"

// ??? links[0]::before;

Here is the scenario:

javascriptcssdompseudo-element

Answer №1

Use ":before" as the second argument in window.getComputedStyle():

console.log(getComputedStyle(document.querySelector('p'), ':before').getPropertyValue('content'));
p::before,
p::after {
  content: ' Test ';
}
<p>Lorem Ipsum</p>

Answer №2

Understanding getComputedStyle() and getPropertyValue()

Retrieve the value of 'content' from the pseudo-element '::after' of the span with class 'search-box' using getComputedStyle().

Answer №3

    document.addEventListener('DOMContentLoaded', function() {
      var widthvalue = 12;
      var customStyle = document.createElement('style');
      customStyle.innerHTML = '.custom-class::before {content: " ! "; color: blue; width: ' + widthvalue + 'px !important;}';
      document.head.appendChild(customStyle);
    });
<div class="custom-class">
        New Title
    </div>

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