listenOnce javascript Code Snippet in 2025

Adds an event listener to an element that will only run the callback the first time the event is triggered.

• Use EventTarget.addEventListener() to add an event listener to an element.
• Use { once: true } as options to only run the given callback once.

const listenOnce = (el, evt, fn) =>
  el.addEventListener(evt, fn, { once: true });

listenOnce(
  document.getElementById('my-id'),
  'click',
  () => console.log('Hello world')
); // 'Hello world' will only be logged on the first click