MutationRecord: attributeName property
The MutationRecord
read-only property attributeName
contains the name of a changed attribute belonging to a node that is observed by a MutationObserver
.
Value
Examples
Get last updated attribute name
In the following example, there are four buttons: two change the style
attribute of the h1
element, and two change the class
attribute of the h1
element. The script uses a MutationObserver
to detect the changes and will update the text below to the name of the last attribute that was changed.
HTML
html
<h1 class="blue" style="color:black;" id="hiMom">Hi, Mom!</h1>
<button id="redButton">Set class to "red"</button>
<button id="blueButton">Set class to "blue"</button>
<button id="whiteButton">Set style to "color:white;"</button>
<button id="blackButton">Set style to "color:black;"</button>
<p id="log">Updated attribute name:</p>
CSS
css
.red {
background-color: red;
}
.blue {
background-color: blue;
}
JavaScript
js
const hiMom = document.querySelector("#hiMom");
const redButton = document.querySelector("#redButton");
const blueButton = document.querySelector("#blueButton ");
const whiteButton = document.querySelector("#whiteButton");
const blackButton = document.querySelector("#blackButton");
const log = document.querySelector("#log");
redButton.addEventListener("click", () => {
hiMom.classList.add("red");
hiMom.classList.remove("blue");
});
blueButton.addEventListener("click", () => {
hiMom.classList.add("blue");
hiMom.classList.remove("red");
});
whiteButton.addEventListener("click", () => {
hiMom.style.color = "white";
});
blackButton.addEventListener("click", () => {
hiMom.style.color = "black";
});
function logLastAttr(mutationRecordArray) {
for (const record of mutationRecordArray) {
if (record.type === "attributes") {
log.textContent = `Updated attribute name: ${record.attributeName}`;
}
}
}
const observer = new MutationObserver(logLastAttr);
observer.observe(hiMom, { attributes: true });
Result
Specifications
Specification |
---|
DOM Standard # ref-for-dom-mutationrecord-attributename② |
Browser compatibility
BCD tables only load in the browser