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StylePropertyMapReadOnly: size property - Web APIs | MDN
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StylePropertyMapReadOnly: size property
Limited availability
This feature is not Baseline because it does not work in some of the most widely-used browsers.
The size read-only property of the
StylePropertyMapReadOnly interface returns an unsigned long integer
containing the size of the StylePropertyMapReadOnly object.
Value
An unsigned long integer.
Examples
Here we use the size property to return the total entries within the button elements
computedStyleMap.
js
// 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
Specifications
| Specification |
|---|
| CSS Typed OM Level 1 # dom-stylepropertymapreadonly-size |
Browser compatibility
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