This feature is not Baseline because it does not work in some of the most widely-used browsers.
The toSum() method of the CSSNumericValue interface converts the object's value to a CSSMathSum object to values of the specified unit.
toSum(units)
unitsThe units to convert to.
A CSSMathSum.
TypeErrorThrown if an invalid type was passed to the method.
let v = CSS.px("23").add(CSS.percent("4")).add(CSS.cm("3")).add(CSS.in("9"));
v.toString(); // => "calc(23px + 4% + 3cm + 9in)"
v.toSum("px", "percent").toString(); // => "calc(1000.39px + 4%)"
| Specification |
|---|
| CSS Typed OM Level 1> # dom-cssnumericvalue-tosum> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
toSum |
66 | 79 | No | 53 | 16.4 | 66 | No | 47 | 16.4 | 9.0 | 66 | 16.4 |
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https://developer.mozilla.org/en-US/docs/Web/API/CSSNumericValue/toSum