Is it possible in JavaScript to listen for a change of attribute value? For example:
var element=document.querySelector('…');
element.addEventListener( ? ,doit,false);
element.setAttribute('something','whatever');
function doit() {
}
I would like to respond to any change in the something attribute.
I have read up on the MutationObserver object, as well as alternatives to that (including the one which uses animation events). As far as I can tell, they are about changes to the actual DOM. I’m more interested in attribute changes to a particular DOM element, so I don’t think that’s it. Certainly in my experimenting it doesn’t seem to work.
I would like to do this without jQuery.
Thanks
ベストアンサー1
You need MutationObserver, Here in snippet I have used setTimeout to simulate modifying attribute
var element = document.querySelector('#test');
setTimeout(function() {
element.setAttribute('data-text', 'whatever');
}, 5000)
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(mutation) {
if (mutation.type === "attributes") {
console.log("attributes changed");
// Example of accessing the element for which
// event was triggered
mutation.target.textContent = "Attribute of the element changed";
}
console.log(mutation.target);
});
});
observer.observe(element, {
attributes: true //configure it to listen to attribute changes
});<div id="test">Dummy Text</div>Additionally, mutation.target property gives the reference to mutated/changed node.