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WheelEvent: deltaY property - Web APIs | MDN
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WheelEvent: deltaY property
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 WheelEvent.deltaY read-only property is a
double representing the vertical scroll amount in the
WheelEvent.deltaMode unit.
You must check the deltaMode property to determine the unit of the deltaY value. Do not assume that the deltaY value is specified in pixels. Some browsers, for compatibility reasons, may return different units for the deltaY value depending on whether deltaMode has been accessed, to accommodate for websites not explicitly checking the deltaMode property.
Value
A number.
Examples
js
const syntheticEvent = new WheelEvent("syntheticWheel", {
deltaY: 4,
deltaMode: 0,
});
console.log(syntheticEvent.deltaY);
Specifications
| Specification |
|---|
| UI Events # dom-wheelevent-deltay |
Browser compatibility
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