The unitType property of the SVGLength interface that represents type of the value as specified by one of the SVG_LENGTHTYPE_* constants defined on this interface.
One of the following:
SVGLength.SVG_LENGTHTYPE_UNKNOWN (0)SVGLength.SVG_LENGTHTYPE_NUMBER (1)SVGLength.SVG_LENGTHTYPE_PERCENTAGE (2)SVGLength.SVG_LENGTHTYPE_EMS (3)SVGLength.SVG_LENGTHTYPE_EXS (4)SVGLength.SVG_LENGTHTYPE_PX (5)SVGLength.SVG_LENGTHTYPE_CM (6)SVGLength.SVG_LENGTHTYPE_MM (7)SVGLength.SVG_LENGTHTYPE_IN (8)SVGLength.SVG_LENGTHTYPE_PT (9)SVGLength.SVG_LENGTHTYPE_PC (10)Here's an example of how to access the unitType property:
// Get an SVGLength object
const svg = document.querySelector("svg");
// Assume `length` is an instance of SVGLength
const length = svg.createSVGLength();
// Set the length value
length.newValueSpecifiedUnits(SVGLength.SVG_LENGTHTYPE_PERCENTAGE, 20);
// Check the unit type
console.log(length.unitType); // Output: 2 (SVG_LENGTHTYPE_PERCENTAGE)