DOM: Navigate DOM Tree

Here is how to navigate the DOM tree. That is, if you have a node, you can get its parent node, sibling node, or children nodes.

Get Parent Node

node.parentElement

Value is the parent of node, or null.

Get Previous/Next Sibling

element.previousElementSibling

Value is the previous sibling that's not a whitespace node. null if none.

element.nextElementSibling

Value is the next sibling that's not a whitespace node. null if none.

document.getElementsByTagName("p")[0] .nextElementSibling.style.color = "green";

Get First/Last Child

element.firstElementChild

Value is the first non-whitespace child node of element, or null if none.

element.lastElementChild

Value is the last non-whitespace child node of element, or null if none.

Get Child Nodes

element.children

Value is a live collection of all non-whitespace children of element. [see DOM: Whitespace Nodes]

const x = document.body .children;
Array.from ( x ) .forEach ((x => { x.style.color="green" }));

• [see DOM: What Does Live Object Mean?]
• [see DOM: NodeList vs HTMLCollection]