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web api interface

CSSMathValue

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The CSSMathValue interface of the CSS Typed Object Model API a base class for classes representing complex numeric values.

Interfaces based on CSSMathValue

Below is a list of interfaces based on the CSSMathValue interface.

Instance properties

  • operator
    • : Indicates the operator that the current subtype represents.

Static methods

The interface may also inherit methods from its parent interface, CSSNumericValue.

Instance methods

The interface may also inherit methods from its parent interface, CSSNumericValue.

Examples

We create an element with a width determined using a calc() function, then console.log() the operator.

<div>has width</div>

We assign a width with a calculation

div {
  width: calc(30% - 20px);
}

We add the JavaScript

const styleMap = document.querySelector("div").computedStyleMap();

console.log(styleMap.get("width")); // CSSMathSum {values: CSSNumericArray, operator: "sum"}
console.log(styleMap.get("width").operator); // 'sum'
console.log(styleMap.get("width").values[1].value); // -20
Interactive exampleOpen the canonical MDN source to run this embedded demo.

The CSSMathValue.operator returns "sum" because styleMap.get("width").values[1].value ); is -20: adding a negative number.

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.