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

Sougata Ghosh
Sougata Ghosh
6,096 Points
Posted by 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

Liam Clarke
Liam Clarke
19,887 Points

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'; 
       }
    }
});