Definition
UI Events defines WheelEvent
[Exposed=Window]
interface WheelEvent : MouseEvent {
constructor(DOMString type, optional WheelEventInit eventInitDict = {});
// DeltaModeCode
const unsigned long DOM_DELTA_PIXEL = 0x00;
const unsigned long DOM_DELTA_LINE = 0x01;
const unsigned long DOM_DELTA_PAGE = 0x02;
readonly attribute double deltaX;
readonly attribute double deltaY;
readonly attribute double deltaZ;
readonly attribute unsigned long deltaMode;
};