CSSStyleValue: toString() method

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

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The toString() method of the CSSStyleValue interface is a stringifier that returns the value formatted as a string of standard CSS text.

Syntax

js
toString()

Parameters

None.

Return value

A string.

Description

The exact serialization of the object to a string depends on how the CSSStyleValue object was obtained:

  • If the object was created by parsing a CSS string, such as with CSSStyleValue.parse(), the method returns the original string that was parsed.
  • If the object was constructed directly, such as with a CSS factory function or a subclass constructor, the returned string is generated according to serialization rules specific to that subclass.
  • If the object was read from the CSSOM, such as with Element.computedStyleMap() or HTMLElement.attributeStyleMap, the returned string follows the CSSOM serialization rules.

For more information about serialization rules see When and how values are serialized in CSS value serialization.

Examples

Basic usage

js
// Parsed from a string: returns the original string
const length1 = CSSStyleValue.parse("42.0px");
length1.toString(); // "42.0px"

// Constructed directly with a CSS factory function: subclass-specific serialization
const length2 = CSS.px(42.0);
length2.toString(); // "42px"

// Read from the CSSOM: follows CSSOM serialization rules
const element = document.createElement("div");
element.style.width = "42.0px";
const length3 = element.attributeStyleMap.get("width");
length3.toString(); // "42px"

Specifications

Specification
CSS Typed OM Level 1
# stylevalue-serialization

Browser compatibility

See also