Why is the DOMSubtreeModified event deprecated in DOM level 3?

Why is the DOMSubtreeModified event deprecated and what are we supposed to use instead?



If you scroll down a bit, you see:

Warning! The MutationEvent interface was introduced in DOM Level 2 Events, but has not yet been completely and interoperably implemented across user agents. In addition, there have been critiques that the interface, as designed, introduces a performance and implementation challenge. A new specification is under development with the aim of addressing the use cases that mutation events solves, but in more performant manner. Thus, this specification describes mutation events for reference and completeness of legacy behavior, but deprecates the use of both the MutationEvent interface and the MutationNameEvent interface.

The replacement API is mutation observers, which are fully specified in the DOM Living Standard that supercedes all of the DOM level X silliness.


I think the replacement will be mutation observers: https://developer.mozilla.org/en-US/docs/Web/API/MutationObserver

var whatToObserve = {childList: true, attributes: true, subtree: true, attributeOldValue: true, attributeFilter: ['class', 'style']};
var mutationObserver = new MutationObserver(function(mutationRecords) {
  $.each(mutationRecords, function(index, mutationRecord) {
    if (mutationRecord.type === 'childList') {
      if (mutationRecord.addedNodes.length > 0) {
        //DOM node added, do something
      else if (mutationRecord.removedNodes.length > 0) {
        //DOM node removed, do something
    else if (mutationRecord.type === 'attributes') {
      if (mutationRecord.attributeName === 'class') {
        //class changed, do something
mutationObserver.observe(document.body, whatToObserve);


Recent Questions

Top Questions

Home Tags Terms of Service Privacy Policy DMCA Contact Us

©2020 All rights reserved.