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

Lucan Fraser
.a{fill-rule:evenodd;}techdegree seal-36
Lucan Fraser
Full Stack JavaScript Techdegree Graduate 16,816 Points

DOM Script challenge

Why would this code not run. it appears to me to be the correct 'if()' condition!

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) {

           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>

1 Answer

Antonio De Rose
Antonio De Rose
20,885 Points

nope this is wrong, how can it be correct.

Have you understood the question, I try re-phrase

Quite simple.

Compare the value which have had been put inside the textbox, which then is stored into a variable called index, which you have perfectly doing, but, with whom are you comparing.

question clearly states - "We want to be able to enter a 0, 1 or 2 in the text field to embolden the list item with the corresponding index"

const laws = document.getElementsByTagName('li');  // this returns an array, and it will have a count of 3, as there 3 li
// index is a integer, can you compare an integer with an array
// it will have to apples with apples, when it comes to comparson

// the main reason to loop, the laws, is to break down the individual value
// first time the loop will a value, second time another third time another

// that is storing in the variable 'i', array starts from 0
// what is assumed as entered in the textbox 0 or 1 or 2

// try it, let me know, if you stuck
Lucan Fraser
.a{fill-rule:evenodd;}techdegree seal-36
Lucan Fraser
Full Stack JavaScript Techdegree Graduate 16,816 Points

I think I understand conceptually. I had to paste the code into my editor to see what was being returned. The item in the array was being compared to the input value....i.e ( 0 === <li>For every action, there is an equal and opposite reaction.</li>). Which was what you had stated, so i change it to ( index === i) thanks for the assistance.