Business
Jobs
  • About Us
  • Solutions
    • Job Postings
      Post your job and receive qualified candidates in 48h.
    • Candidate Assessments
      500+ technical and psychological tests, plus anti-fraud.
    • Headhunting
      Tailor-made executive search from start to finish.
    • Payroll + EOR
      Payroll dispersal and EOR across 15+ LATAM countries.
  • Pricing
  • Jobs

0

283
Views
Javascript - For loop not iterating through last item when changing class name

I'm trying to change the classname if certain links in my navigation, but the doesn't seem to want to iterate through the last item. The commented out hardcoded section works just fine

HTML

<ul id="nav-list">
    <li class="not-current"><a href="home.html">Home</a></li>
    <li class="current"><a 
    href="documentation.html">Documentation</a></li>
    <li class="not-current"><a href="designs.html">Designs and 
    Wireframes</a></li>
    <li id="last-nav-item" class="not-current"><a 
    href="meeting.html">Book a Meeting</a></li>
</ul>

JavaScript

var notCurrentLinks = document.getElementsByClassName('not- 
current');

function openMobileMenu() {
    for (let i = 0; i < (notCurrentLinks.length); i++) {
        console.log('Worked ' + (i + 1) + ' time(s)');
        notCurrentLinks[i].className = 'm-not-current';
    }            
//Hardcoding below seems to work
//notCurrentLinks[0].className = 'm-not-current';
//notCurrentLinks[1].className = 'm-not-current';
//notCurrentLinks[2].className = 'm-not-current';
notCurrentLinks = document.getElementsByClassName('m-not- 
current');
}

The console returns

  • Worked 1 time(s)
  • Worked 2 time(s)
about 4 years ago · Juan Pablo Isaza
1 answers
Answer question

0

It's a live collection, meaning if you loop it and you change its collected items in the loop the loop will skip nodes here and there.

// example
document.body.innerHTML = '<p class="p">p</p><p class="p">p</p>';

const p = document.getElementsByClassName('p');

p.length; // 2

p[0].className = '';

p.length; // 1

Live collections are synchronous and reflecting the current state of the collection. If you don't want this to happen you need static collection instead:

// all o with class `p`
const p = document.querySelectorAll('.p');

Now even if p[0].className = '' happens, that collection will still have that previously .p element in it.

about 4 years ago · Juan Pablo Isaza Report
Answer question
Find remote jobs

Discover the new way to find a job!

Top jobs
Top job categories
Business
Post vacancy Pricing Sales
Legal
Terms and conditions Privacy policy
© 2026 PeakU Inc. All Rights Reserved.
Andres GPT
Show me some job opportunities
There's an error!