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JavaScript JavaScript and the DOM (Retiring) Traversing the DOM Sibling Traversal

Posted by Phillip Lewis
Phillip Lewis
8,549 Points

I know I need to use the insertBefore method but not quite sure how to go about it.

Is part of the problem to give a paragraph a class of highlight? It says to do it on line five. Not sure how that is supposed to be done.

app.js 
const list = document.getElementsByTagName('ul')[0];

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {

  }
});
index.html 
<!DOCTYPE html>
<html>
    <head>
        <title>JavaScript and the DOM</title>
    </head>
    <link rel="stylesheet" href="style.css" />
    <body>
        <section>
            <h1>Making a Webpage Interactive</h1>
            <p>Things to Learn</p>
            <ul>
                <li><p>Element Selection</p><button>Highlight</button></li>
                <li><p>Events</p><button>Highlight</button></li>
                <li><p>Event Listening</p><button>Highlight</button></li>
                <li><p>DOM Traversal</p><button>Highlight</button></li>
            </ul>
        </section>
        <script src="app.js"></script>
    </body>
</html>

1 Answer

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

:point_right: Adding the class to the paragraph before the button is exactly what the task requires.

So you want to select the paragraph element which you know is immediately previous to the button itself. Since the provided code already filters out only events on buttons, you can get the previousElementSibling of the event target to get the paragraph, and then use that to set the class name.

You will not need to insert any elements for this task.