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MathMLElement: dataset property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨January 2023⁩.

The dataset read-only property of the MathMLElement interface provides read/write access to custom data attributes (data-*) on elements. It exposes a map of strings (DOMStringMap) with an entry for each data-* attribute.

The dataset property itself can be read, but not directly written. Instead, all writes must be to the individual properties within the dataset, which in turn represent the data attributes.

Value

A DOMStringMap.

Examples

<div>
  <math>
    <msup id="equation" data-value="-1" data-equation="euler">
      <mi>e</mi>
      <mi>iπ</mi>
    </msup>
    <mo>+</mo>
    <mn>1</mn>
    <mo>=</mo>
    <mn>0</mn>
  </math>
</div>
const el = document.querySelector("#equation");

console.log(el.dataset.value); // "-1"
console.log(el.dataset.equation); // "euler"

Result

Specifications

Specification
HTML>
# dom-dataset-dev>

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Opera Safari Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet WebView Android WebView on iOS
dataset 109 109 71 95 13.1 109 79 74 13.4 21.0 109 13.4

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/MathMLElement/dataset