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JavaScript JavaScript and the DOM (Retiring) Making Changes to the DOM Changing Element Attributes

Posted by Kevin Barnes
Kevin Barnes
18,352 Points

input.className returns blank

Hey,

Followed along with this video, and it's all good. I'm just curious though, when I used the console to get the class (input.className) it just showed "".

The HTML input element has a class assigned to it, I'm just curious why this wouldn't work? Has something changed since this video was made?

Kevin Barnes
Kevin Barnes
18,352 Points

Needless to say, this is causing issues in later videos where getting inputs by their class name keeps returning null. I would love some help here because it's driving me insane. I've checked the code over so many times and I can't see any issues, just for some reason the browser thinks the inputs don't have a class name.

P.S. This even happens when opening a new workspace on the video, so I'm 99.9% sure it's not a problem with the code.

<!DOCTYPE html>
<html>
  <head>
    <title>JavaScript and the DOM</title>
    <link rel="stylesheet" href="css/style.css">
  </head>
  <body>
    <h1 id="myHeading">JavaScript and the DOM</h1>
    <p>Making a web page interactive</p>    
    <button id="toggleList">Hide list</button>
    <div class="list">
      <p class="description">Things that are purple:</p>
      <input type="text" class"description">
      <button class="description">Change list description</button>
      <ul>
        <li>grapes</li>
        <li>amethyst</li>
        <li>lavender</li>
        <li>plums</li>
      </ul>
      <input type="text" class"addItemInput">
      <button class="addItemButton">Add item</button>
    </div>
    <script src="app.js"></script>
  </body>
</html>

const toggleList = document.getElementById('toggleList');
const listDiv = document.querySelector('.list');
const descriptionInput = document.querySelector('input.description');
const descriptionP = document.querySelector('p.description');
const descriptionButton = document.querySelector('button.description');
const addItemInput = document.querySelector('input.addItemInput');
const addItemButton = document.querySelector('button.addItemButton');


toggleList.addEventListener('click', () => {
  if (listDiv.style.display == 'none') {
    toggleList.textContent = 'Hide list';
    listDiv.style.display = 'block';
  } else {
    toggleList.textContent = 'Show list';
    listDiv.style.display = 'none';   
  }
})

descriptionButton.addEventListener('click', () => {
  descriptionP.innerHTML = descriptionInput.value + ':';                        
})

addItemButton.addEventListener('click', () => {
  let ul = document.getElementsByTagName('ul')[0];
  let li = document.createElement('li');
  li.textContent = addItemInput.value;
  ul.appendChild(li);
})

1 Answer

Kevin Barnes
Kevin Barnes
18,352 Points
Kevin Barnes
Kevin Barnes
18,352 Points

You know what... I'm an idiot - just noticed the lack of a '=' when declaring the classes.