Question

Some DOM selection methods like getElementsByClassName() are common to HTMLDocument and HTMLElement.

Is there any common interface for inheriting common selection methods? ( as an example Node interface provides some common methods).

document.getElementsByClassName("test");

element.getElementsByClassName("test");

Answer 1

Both inherit through the prototype chain from Node, but it appears that those particular methods aren’t defined in a common interface; they appear independently in each of Element and Document.

Object --> Node --> Element --> HTMLElement
             \----> Document --> HTMLDocument