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

Posted by musab abdi
musab abdi
7,110 Points

javascript

help me solve this task such that the number you put in input field changes the font of the corresponding li element

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>

1 Answer

Jason Miller
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Jason Miller
Full Stack JavaScript Techdegree Graduate 32,220 Points
Jason Miller
.a{fill-rule:evenodd;}techdegree seal-36
Jason Miller
Full Stack JavaScript Techdegree Graduate 32,220 Points

Hey musab abdi,

This challenge is asking you to check if the value the user enters in the input const index = parseInt(indexText.value, 10); is an index in the HTML collection const laws = document.getElementsByTagName('li');. HTML collections are like arrays which means they are zero indexed. If the value the user enters is an index in the collection it will make the font-weight: bold; if not it will make the font-weight: normal.

so the answer is:

       if (index === i) {

           law.style.fontWeight = 'bold';
       } else {
           law.style.fontWeight = 'normal';
       }