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JavaScript DOM Scripting By Example Editing and Filtering Names Fix DOM Manipulation Code

Zachary Baca
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Zachary Baca
Full Stack JavaScript Techdegree Student 8,144 Points

I don't know what else to do after checking if a law element exists?

I updated the if statement to check if a law exists once it passes the for loop, and then if it exists, it shows in the code where the style is applied. The code looks fine to me, but when I test it, it is still applying the style to the whole list. I thought e.preventDefault would help, but that still didn't do anything.

app.js
const laws = document.getElementsByTagName('li');
const indexText = document.getElementById('boldIndex');
const button = document.getElementById('embolden');

button.addEventListener('click', (e) => {
    const index = parseInt(indexText.value, 10);

    for (let i = 0; i < laws.length; i += 1) {
       let law = laws[i];

       // replace 'false' with a correct test condition on the line below
       if (law) {
           e.preventDefault();
           law.style.fontWeight = 'bold';
       } else {
           law.style.fontWeight = 'normal';
       }
    }
});
index.html
<!DOCTYPE html>
<html>
<head>
  <title>Newton's Laws</title>
</head>
<body>
  <h1>Newton's Laws of Motion</h1>
  <ul>
    <li>An object in motion tends to stay in motion, unless acted on by an outside force.</li>
    <li>Acceleration is dependent on the forces acting upon an object and the mass of the object.</li>
    <li>For every action, there is an equal and opposite reaction.</li>
  </ul>
  <input type="text" id="boldIndex">
  <button id="embolden">Embolden</button>
  <script src="app.js"></script>
</body>
</html>

1 Answer