An event handler is JavaScript code that runs when an event happens. Event handlers can be used to handle and verify user input, user actions, and browser actions:

4 days ago · To react to an event, you attach an event listener to it. This is a code feature that listens out for the event firing. When the event fires, an event handler function (referenced by, or contained …

Jul 11, 2025 · JavaScript Events are actions or occurrences that happen in the browser. They can be triggered by various user interactions or by the browser itself.

Learn how to perform event handling in JavaScript including HTML Event Handler attributes, DOM Level 0 Event Handlers, and DOM Level 2 Event Handlers.

Jul 17, 2025 · To respond to these events, JavaScript uses event handlers, which are functions specifically designed to execute when an event occurs. This relationship is what powers everything …

Feb 7, 2025 · A comprehensive guide to JavaScript event handling, covering event listeners, event types, capturing, bubbling, and more, with practical examples.

When an event occur, you can use a JavaScript event handler (or an event listener) to detect them and perform specific task or set of tasks.

Explore all events in JavaScript with examples. Learn how to handle events efficiently with our complete list of JavaScript event types and usage tips.

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Each browser event handler is registered in a context. In the previous example, we called addEventListener on the window object to register a handler for the whole window. Such a method …