This event is generated when the mouse wheel is rolled down
Parameters
| Name | Explanation |
|---|---|
| Shift | The state of the key or mouse button ssShift: Shift key is pressed ssAlt: Alt key is pressed ssCtrl: Ctrl key is pressed ssLeft: Left mouse button is pressed ssRight: Right mouse button is pressed ssMiddle: Middle mouse button is pressed ssDouble: Mouse has been double clicked |
| Direction | Direction of the scroll. (vikDisable: disables scroll, vikVertical: vertical, vikHorizontal: horizontal) |
Explanation
The MouseWheelDownImage event is generated when the mouse wheel is rolled down. Any code written in this event will execute whenever the mouse wheel is rolled down. Furthermore, by using the Shift parameter, you can determine whether another mouse button was pressed at the same time the mouse wheel was rolled down. In this way, you can write different code that executes if the left mouse button is pressed while the mouse wheel is rolled down or if the right mouse button is pressed while the mouse is rolled down, etc.
Note: The Direction parameter returns the value set in the MouseWheel property.
For more information about the TMouseButton type and the TShiftState type, please refer to the Delphi or C++Builder help documentation.
Differences from ImageKit7/8/9/10 ActiveX
The Shift parameter has been changed to the TShiftState type
The VCL constants have a "v". In ActiveX, the constants are
ikDisable, ikVertical, and ikHorizontal