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JavaScript

Gareth Moore
Gareth Moore
7,724 Points

A helpful thing to keep in mind about addEventListener()

There is an array of Event listeners when you open a web page.

When you use: addEventListener()

You add another event listener (register the event listener) to the array of event listeners already created. Each time an event is triggered, say a 'click', the browser will go through the entire list of event listeners to see if there is a match, and if so, execute the event handler.

This helped me a lot because I had no idea where or how to use event listeners but now, knowing that creating an event listener adds this new event to a list of event listeners, has given me some helpful insight into how they work.

This guy explains it better: https://stackoverflow.com/questions/13156096/where-is-an-event-registered-with-addeventlistener-stored

1 Answer