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

Christopher Lauriano
Christopher Lauriano
Full Stack JavaScript Techdegree Student 3,092 Points

How do you match the value of the index variable to the specific li element number?

I believe I have the start of the conditional correct. I'm just not sure how to match the index value to the corresponding list number.

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 ( index ===  )  {

           law.style.fontWeight = 'bold';
       } else {
           law.style.fontWeight = 'normal';
<!DOCTYPE html>
  <title>Newton's Laws</title>
  <h1>Newton's Laws of Motion</h1>
    <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>
  <input type="text" id="boldIndex">
  <button id="embolden">Embolden</button>
  <script src="app.js"></script>

2 Answers

Louise St. Germain
Louise St. Germain
19,410 Points

Hi Christopher,

You're so close!

index is what the user typed in (you already got that part), and you have to check whether it matches the index into the corresponding list: i. So if those two match up (i.e., you're on the *i*th list item and that matches the index the user gave), turn it bold. If they don't match, make sure it's not bold.

Hope this helps - you are literally one letter away from the solution. :-)