SVGLength: newValueSpecifiedUnits() method

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨July 2015⁩.

The newValueSpecifiedUnits() method of the SVGLength interface resets the value as a number with an associated unitType, thereby replacing the values for all of the attributes on the object.

A constant representing the unit type to which the length's value should be converted. This must be one of the constant values defined for the unitType property, with the exception of SVG_LENGTHTYPE_UNKNOWN.

SVGLength.SVG_LENGTHTYPE_NUMBER: convert to unitless number
SVGLength.SVG_LENGTHTYPE_PERCENTAGE: convert to percentage
SVGLength.SVG_LENGTHTYPE_EMS: convert to em units
SVGLength.SVG_LENGTHTYPE_EXS: convert to ex units
SVGLength.SVG_LENGTHTYPE_PX: convert to pixels
SVGLength.SVG_LENGTHTYPE_CM: convert to centimeters
SVGLength.SVG_LENGTHTYPE_MM: convert to millimeters
SVGLength.SVG_LENGTHTYPE_IN: convert to inches
SVGLength.SVG_LENGTHTYPE_PT: convert to points
SVGLength.SVG_LENGTHTYPE_PC: convert to picas

valueInSpecifiedUnits

The numeric factor for the length value, expressed in the specified unit type.

Return value

None (undefined).

Exceptions

This method may raise a DOMException of one of the following types:

NotSupportedError DOMException: Thrown if unitType is SVG_LENGTHTYPE_UNKNOWN or not a valid unit type constant.
NoModificationAllowedError DOMException: Thrown if SVGLength corresponds to a read-only attribute or when the object itself is read-only.

Examples

Setting a length value with specific units

// Get an SVGLength object
const svg = document.querySelector("svg");
const length = svg.createSVGLength();

// Set a new value with specific units
length.newValueSpecifiedUnits(SVGLength.SVG_LENGTHTYPE_NUMBER, 45);
console.log(length.valueInSpecifiedUnits); // Output: 45
console.log(length.unitType); // Output: 1 (SVG_LENGTHTYPE_NUMBER)
console.log(length.value); // The value converted to the user coordinate system

// Change the value to pixels
length.newValueSpecifiedUnits(SVGLength.SVG_LENGTHTYPE_PX, 100);
console.log(length.valueInSpecifiedUnits); // Output: 100
console.log(length.unitType); // Output: 5 (SVG_LENGTHTYPE_PX)