getElementsByClassName

getElementsByClassName is a DOM method in JavaScript that returns a live HTMLCollection of elements with the specified class name(s). It allows developers to select and manipulate multiple elements in a web page based on their CSS class attribute. This method is commonly used for batch operations like styling, event handling, or content updates on groups of similar elements.

Also known as: getElementsByClassName(), getElementsByClass, getElementsByClassname, getElementsByClassName method, DOM getElementsByClassName

Why learn getElementsByClassName?

Developers should use getElementsByClassName when they need to efficiently select multiple elements sharing a common class for DOM manipulation, such as applying styles to all buttons with a 'btn' class or adding event listeners to form inputs. It's particularly useful in scenarios where querySelectorAll might be overkill for simple class-based selections, though note that it returns a live collection that updates automatically as the DOM changes.

Learning Resources

• docs: MDN Web Docs: getElementsByClassName
• tutorial: W3Schools: getElementsByClassName() Method
• video: JavaScript DOM Tutorial - getElementsByClassName
• tutorial: freeCodeCamp: JavaScript DOM Manipulation