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CSSNamespaceRule: prefix property - Web APIs | MDN
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CSSNamespaceRule: prefix property
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since March 2018.
The read-only prefix property of the CSSNamespaceRule returns a string with the name of the prefix associated to this namespace. If there is no such prefix, it returns an empty string.
Value
A string containing the prefix associated to this namespace. If there is no prefix an empty string.
Examples
The stylesheet includes two namespace rules. The first has no prefix the second the prefix svg. Two CSSNamespaceRule objects will be returned. The value of the prefix property for the first will be an empty string, for the second svg.
css
@namespace url("https://www.w3.org/1999/xhtml");
@namespace svg url("https://www.w3.org/2000/svg");
js
let myRules = document.styleSheets[0].cssRules;
console.log(myRules[0].prefix); // an empty string ""
console.log(myRules[1].prefix); // "svg"
Specifications
| Specification |
|---|
| CSS Object Model (CSSOM) # dom-cssnamespacerule-prefix |
Browser compatibility
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