HTMLCollection

HTMLCollection is a live, ordered collection of HTML elements in the Document Object Model (DOM) that is returned by methods like getElementsByClassName() or getElementsByTagName(). It represents a list of nodes that can be accessed by index or name, and it automatically updates when the DOM changes. Unlike arrays, it has limited built-in methods but provides efficient access to DOM elements.

Also known as: HTML Collection, HTMLCollections, DOM HTMLCollection, HTML NodeList (related but distinct), Element Collection

Why learn HTMLCollection?

Developers should learn HTMLCollection when working with DOM manipulation in JavaScript, as it is commonly returned by native DOM query methods and is essential for efficiently accessing and iterating over groups of elements. It is particularly useful in scenarios like batch updates to elements with the same class or tag, such as styling all paragraphs or handling form inputs, but note that it is live, so changes to the DOM can affect the collection dynamically.

Learning Resources

• docs: MDN Web Docs: HTMLCollection
• tutorial: JavaScript.info: DOM Collections
• tutorial: W3Schools: HTML DOM HTMLCollection
• tutorial: FreeCodeCamp: DOM Manipulation Guide