The WheelEvent interface represents events that occur due to the user moving a mouse wheel or similar input device.
Note: This is the standard wheel event interface to use. Old versions of browsers implemented the non-standard and non-cross-browser-compatible MouseWheelEvent and MouseScrollEvent interfaces. Use this interface and avoid the non-standard ones.
Don't confuse the wheel event with the scroll event:
wheel event doesn't necessarily dispatch a scroll event. For example, the element may be unscrollable at all. Zooming actions using the wheel or trackpad also fire wheel events.scroll event isn't necessarily triggered by a wheel event. Elements can also be scrolled by using the keyboard, dragging a scrollbar, or using JavaScript.wheel event does trigger scrolling, the delta* values in the wheel event don't necessarily reflect the content's scrolling direction.WheelEvent()Creates a WheelEvent object.
This interface inherits properties from its ancestors, MouseEvent, UIEvent, and Event.
WheelEvent.deltaX Read onlyReturns a double representing the horizontal scroll amount.
WheelEvent.deltaY Read onlyReturns a double representing the vertical scroll amount.
WheelEvent.deltaZ Read onlyReturns a double representing the scroll amount for the z-axis.
WheelEvent.deltaMode Read onlyReturns an unsigned long representing the unit of the delta* values' scroll amount.
WheelEvent.wheelDelta Read only Returns an integer (32-bit) representing the distance in pixels.
WheelEvent.wheelDeltaX Read only Returns an integer representing the horizontal scroll amount.
WheelEvent.wheelDeltaY Read only Returns an integer representing the vertical scroll amount.
Note: Element: mousewheel event has additional documentation about the deprecated properties wheelDelta, wheelDeltaX, wheelDeltaY.
This interface doesn't define any specific methods, but inherits methods from its ancestors, MouseEvent, UIEvent, and Event.
wheel eventMouseScrollEvent