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

Greg Schudel
Greg Schudel
4,090 Points

Not sure what I'm getting wrong here

Really frustrated with how to resolve this. I've looked at forums and I'm honestly not sure how to get to the right answer or this working with just one line of code.

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[i] === index ) {  

           law.style.fontWeight = 'bold';

       } else {
           law.style.fontWeight = 'normal';
       }
    }
});
<!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>

what am I misunderstanding??? Do I need to study the properties more? Am I missing the point of an if conditional??

1 Answer

law becomes the current element in the loop, when you only really need the current value of the iterator. Then if that equals the number of the user submitted index..

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

       if ( i === index ) {  
           law.style.fontWeight = 'bold';
       } else {
           law.style.fontWeight = 'normal';
       }
    }
Greg Schudel
Greg Schudel
4,090 Points

what's the iterator? i? I thought that stood for index. I've never seen it used outside of those brackets, hence why I was so confused.

var i is what I meant yes, i call it the iterator because it is what helps us count or iterate through the array. But it does provide an index when used like laws[i] :)