Equivalent to DOMNodeInserted DOMNodeRemoved with MutationObserver?

Question

I currently have the code:

$('.example').bind('DOMNodeInserted DOMNodeRemoved', function(event) {
    ....
});

Which works fine, but it's not very effective and has been deprecated since then. What is the best way to do this?

I searched for MutationObserver, but does this code work?

It gives the error "is mutation.addedNodesnot a function." I will also need removedNodes.

var observer = new MutationObserver(function(mutations) {
      mutations.forEach(function(mutation) {
        mutation.addedNodes.forEach(function(node) {
          if (node.className == 'example') {
              ....
          }
        });
      });
    });
    observer.observe(document, {
      childList: true,
      subtree: true,
      attributes: false,
      characterData: false,
    });

Answer 1

.addedNodesreturns a NodeListnot a Array, which does not have a method .forEach(). Try using Array.prototype.slice()cast .addedNodesto Array, which has a method.forEach()

var observer = new MutationObserver(function(mutations) {
      mutations.forEach(function(mutation) {
        var nodes = Array.prototype.slice.call(mutation.addedNodes);
        nodes.forEach(function(node) {
          if (node.parentElement.className == "example") {
              alert(node.parentElement.className)
          }
        });
      });
    });
    observer.observe(document.querySelector(".example"), {
      childList: true,
      subtree: true,
      attributes: false,
      characterData: false,
    });

var el = document.createElement("div");
el.className = "example-child";
document.querySelector(".example").appendChild(el)

<div class="example"></div>

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