When searching for nodes through the entire DOM, it best to use XPath to do so. Often, a for loop is used, as per the following example where h2, h3 and h4 elements are being searched for:
function myJS(){ let elements = document.getElementsByTagName("*"); for(let i = 0; i < elements.length; i++) { if(elements[i].tagName.match("/^h[2-4]$/i")) { // Do something with the node that was found } }}
Instead of using this for loop, an XPath iterator object could be used to obtain the same result, only much more efficiently:
function myJS(){ let allHeadings = document.evaluate("//h2|//h3|//h4", document, null, XPathResult.ORDERED_NODE_ITERATOR_TYPE, null); let singleheading; while(singleheading = allHeadings.iterateNext()) { ...
