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42. DOM Manipulation & Event Delegation

Efficient event handling and avoiding memory leaks.

1 min read3 questionsup to 50 XPtopic 42/50

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Event delegation places a single event listener on a parent element to handle events from present and future child elements via event bubbling.

js
container.addEventListener("click", (e) => {
  const btn = e.target.closest("button[data-action]");
  if (btn) handleAction(btn.dataset.action);
});

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Check your understanding

  1. 1. What mechanism enables event delegation?

  2. 2. Which method safely sets text without XSS injection risk?

  3. 3. Why use e.target.closest('selector') in delegation?

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