Element: pseudo() method
{{SeeCompatTable}}
{{APIRef("DOM")}}.
The pseudo() method of the {{domxref("Element")}} interface returns a {{domxref("CSSPseudoElement")}} object representing the CSS pseudo-element of the specified type associated with the element.
Provided its type parameter contains a valid pseudo-element type, pseudo() will always return a CSSPseudoElement instance, even if that pseudo-element hasn't been generated on the calling element.
Syntax
pseudo(type)
Parameters
type- : A string representing the type of pseudo-element to return a representation of. Valid values are:
- {{cssxref("::after")}}
- {{cssxref("::before")}}
- {{cssxref("::marker")}}
- : A string representing the type of pseudo-element to return a representation of. Valid values are:
Return value
A {{domxref("CSSPseudoElement")}} object instance, or null if type is not equal to a valid pseudo-element type.
Examples
Basic usage
In this example, we demonstrate basic usage of the pseudo() method.
HTML
We include a {{htmlelement("p")}} element containing text, and an {{htmlelement("output")}} element to log output from JavaScript.
<p>New York's hottest club is...</p>
<output></output>
CSS
We give the <p> element's {{cssxref("::after")}} pseudo-element some {{cssxref("content")}} and apply some basic styles to both.
body {
width: 80%;
margin: 0 auto;
}
p {
background-color: violet;
padding: 20px;
}
p::after {
content: "Crease";
background-color: cadetblue;
padding: 20px;
}
JavaScript
In our script, we grab references to our <p> and <output> elements, and retrieve a CSSPseudoElement representing the <p> element's ::after pseudo-element via the pseudo() method. We then log some details of the pseudo-element to our <output> element. We also include some rudimentary error handling via a try...catch structure, to print an error message in non-supporting browsers.
const pElem = document.querySelector("p");
const output = document.querySelector("output");
try {
const pseudoElem = pElem.pseudo("::after");
output.textContent = `${pseudoElem.type} pseudo-element. Parent: <${pseudoElem.parent.tagName.toLowerCase()}>`;
} catch (e) {
output.textContent = `Your browser doesn't support CSSPseudoElement and/or the pseudo() method: ${e}`;
}
Result
{{embedlivesample("basic", "100%", 200)}}
Specifications
{{Specifications}}
Browser compatibility
{{Compat}}
See also
- {{DOMxRef("CSSPseudoElement.pseudo()")}}
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