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JavaScript JavaScript and the DOM (Retiring) Getting a Handle on the DOM Practice Selecting Elements

Posted by Matt Winer
Matt Winer
4,023 Points

Seems simple but I can't get it.

Did I miss something on how to select a child element using document.getElementsByTagName();? I am supposed to select all of the link elements inside the <nav>

js/app.js 
let navigationLinks = 
let galleryLinks;
let footerImages;
index.html 
<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title>Nick Pettit | Designer</title>
    <link rel="stylesheet" href="css/normalize.css">
    <link href='http://fonts.googleapis.com/css?family=Changa+One|Open+Sans:400italic,700italic,400,700,800' rel='stylesheet' type='text/css'>
    <link rel="stylesheet" href="css/main.css">
    <link rel="stylesheet" href="css/responsive.css">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
  </head>
  <body>
    <header>
      <a href="index.html" id="logo">
        <h1>Nick Pettit</h1>
        <h2>Designer</h2>
      </a>
      <nav>
        <ul>
          <li><a href="index.html" class="selected links">Portfolio</a></li>
          <li><a href="about.html" class ="links">About</a></li>
          <li><a href="contact.html" class ="links">Contact</a></li>
        </ul>
      </nav>
    </header>
    <div id="wrapper">
      <section>
        <ul id="gallery">
          <li>
            <a href="img/numbers-01.jpg">
              <img src="img/numbers-01.jpg" alt="">
              <p>Experimentation with color and texture.</p>
            </a>
          </li>
          <li>
            <a href="img/numbers-02.jpg">
              <img src="img/numbers-02.jpg" alt="">
              <p>Playing with blending modes in Photoshop.</p>
            </a>
          </li>
        </ul>
      </section>
      <footer>
        <a href="http://twitter.com/nickrp"><img src="img/twitter-wrap.png" alt="Twitter Logo" class="social-icon"></a>
        <a href="http://facebook.com/nickpettit"><img src="img/facebook-wrap.png" alt="Facebook Logo" class="social-icon"></a>
        <p>&copy; 2016 Nick Pettit.</p>
      </footer>
    </div>
  <script src="js/app.js"></script>
  </body>
</html>

2 Answers

Juan Martin
Juan Martin
14,335 Points
Juan Martin
Juan Martin
14,335 Points

Hello Matt,

You can achieve this real quick using querySelectorAll to target all descendant elements using css sintax, in this case it would be the anchor elements that are descendants of the nav element:

let navigationLinks = document.querySelectorAll("nav a");

Hope this helps :)

Umesh Ravji
Umesh Ravji
42,386 Points
Umesh Ravji
Umesh Ravji
42,386 Points

Hi Matt, you are supposed to select all the a elements inside the nav element, but only those ones, not the ones inside the ul and footer elements.

let navigationLinks = document.getElementsByTagName('a');

If you run that code, you will get Bummer! Was expecting 3 links not 8 because it's finding all of the a elements on the page, and not just those inside the nav element.

One way of doing this is to get the nav element, and then call the getElementsByTagName() method on that:

let navigationLinks = document.getElementsByTagName('nav')[0].getElementsByTagName('a');

If you're family with the document.querySelectorAll() method, you can come up with a much more elegant solution :)

[Edit] Oh wells, someone else just posted it :p