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StylePropertyMapReadOnly: size property - Web APIs | MDN
StylePropertyMapReadOnly: size property Limited availability
The size
read-only property of the
StylePropertyMapReadOnly
interface returns an unsigned long integer
containing the size of the StylePropertyMapReadOnly
object.
An unsigned long integer.
Here we use the size property to return the total entries within the button elements
computedStyleMap
.
// grab our element
const buttonEl = document.querySelector("button");
// we can retrieve all computed styles with `computedStyleMap`
const allComputedStyles = buttonEl.computedStyleMap();
// use size to get the total styles within the map
const amountStyles = allComputedStyles.size;
console.log(amountStyles); // logs 338