Limited availability
The CSSMathSum interface of the CSS Typed Object Model API represents the result obtained by calling add(), sub(), or toSum() on CSSNumericValue.
A CSSMathSum is the object type returned when the StylePropertyMapReadOnly.get() method is used on a CSS property whose value is created with a calc() function.
CSSMathSum() Experimental
Creates a new CSSMathSum object.
CSSMathSum.values
Returns a CSSNumericArray object which contains one or more CSSNumericValue objects.
The interface may also inherit methods from its parent interface, CSSMathValue.
The interface may also inherit methods from its parent interface, CSSMathValue.
We create an element with a width determined using a calc() function, then console.log() the operator and values, and dig into the values a bit.
We assign a width
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); // CSSNumericArray {0: CSSUnitValue, 1: CSSUnitValue, length: 2}
console.log(styleMap.get("width").values[0]); // CSSUnitValue {value: 30, unit: "percent"}
console.log(styleMap.get("width").values[0].value); // 30
console.log(styleMap.get("width").values[0].unit); // 'percent'
console.log(styleMap.get("width").values[1]); // CSSUnitValue {value: -20, unit: "px"}
console.log(styleMap.get("width").values[1].value); // -20
console.log(styleMap.get("width").values[1].unit); // 'px'
The specification is still evolving. In the future we may write the last three lines as:
console.log(styleMap.get("width").values[1]); // CSSMathNegate {value: CSSUnitValue, operator: "negate"}
console.log(styleMap.get("width").values[1].value); // CSSUnitValue {value: 20, unit: "px"}
console.log(styleMap.get("width").values[1].value.unit); // 'px'
RetroSearch is an open source project built by @garambo | Open a GitHub Issue
Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo
HTML:
3.2
| Encoding:
UTF-8
| Version:
0.7.4