OnMouseWheel Method

ScrollableControl.OnMouseWheel Method

Raises the MouseWheel event.

Namespace: System.Windows.Forms
Assembly: System.Windows.Forms (in system.windows.forms.dll)

virtual void OnMouseWheel (
	MouseEventArgs^ e
) override
protected void OnMouseWheel (
	MouseEventArgs e
protected override function OnMouseWheel (
	e : MouseEventArgs



A MouseEventArgs that contains the event data.

If the vertical scroll bar is visible, which means that the VScroll property is set to true, the mouse wheel scrolls through the ScrollableControl control vertically. However, if only the horizontal scroll bar is visible, which means that the VScroll is set to false and the HScroll property to set to true, the mouse wheel scrolls horizontally.

Raising an event invokes the event handler through a delegate. For more information, see Raising an Event.

The OnMouseWheel method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

Notes to Inheritors When overriding OnMouseWheel in a derived class, be sure to call the base class’s OnMouseWheel method so that registered delegates receive the event.

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.

.NET Framework

Supported in: 2.0, 1.1, 1.0

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