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

Jeremy Barnes
Jeremy Barnes
8,317 Points
Posted by Jeremy Barnes
Jeremy Barnes
8,317 Points

Can't figure out if statement for bolding li element that corresponds to the numerical input field.

I can't figure out which if statement to test here. Can you help with the answer? thanks!

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 (index === law[i]) {

           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

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

There's only one "if" statement, and you have the right idea about testing the input value that was already conveniently converted into a number and stored in "index". But instead of comparing that number to an element, just compare it directly to the loop variable.

Jeremy Barnes
Jeremy Barnes
8,317 Points
Jeremy Barnes
Jeremy Barnes
8,317 Points

Thanks Steven! I had tried index === [i] and it wasn't working but now I realize that the brackets brought in an array value. Appreciate your help.