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Why does event delegation improve performance in list item click handling in a large unordered list?

Asked on Dec 10, 2025

Answer

Event delegation improves performance by attaching a single event listener to a parent element instead of adding separate listeners to each child element. This is particularly beneficial in a large unordered list where many items might need individual event handling.

<!-- BEGIN COPY / PASTE -->
        document.querySelector('ul').addEventListener('click', function(event) {
            if (event.target.tagName === 'LI') {
                console.log('List item clicked:', event.target.textContent);
            }
        });
        <!-- END COPY / PASTE -->

Additional Comment:

The code attaches a single click event listener to the "ul" element.
Inside the event handler, it checks if the event target is an "li" element.
This approach reduces memory usage and improves performance by minimizing the number of event listeners.
Event delegation leverages event bubbling, allowing the parent to handle events from its children.

✅ Answered with JavaScript best practices.

Ask any question about JavaScript here... and get an instant response.

Why does event delegation improve performance in list item click handling in a large unordered list?

Asked on Dec 10, 2025

Answer

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