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

Sougata Ghosh
Sougata Ghosh
6,096 Points

Dom manipulating

How do i do this

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 (false) {

           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>

2 Answers

In this challenge you need to change the false with the condition of:

if the entered number is equal to the iterated number of list items, set the weight to bold.

So that is:

if the index is equal to the list item number, set the weight to bold

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);  // This is our input field 

    for (let i = 0; i < laws.length; i += 1) {  // This is the iteration through the list items
       let law = laws[i]; 

       if ( i === index ) {  // If our input field is equal to the iterated list item

           law.style.fontWeight = 'bold';  // Set the weight bold
       } else {
           law.style.fontWeight = 'normal'; 
       }
    }
});