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ButtonBase.OnKeyDown(KeyEventArgs) Method

Definition

Raises the OnKeyUp(KeyEventArgs) event.

protected:
 override void OnKeyDown(System::Windows::Forms::KeyEventArgs ^ kevent);
protected override void OnKeyDown (System.Windows.Forms.KeyEventArgs kevent);
override this.OnKeyDown : System.Windows.Forms.KeyEventArgs -> unit
Protected Overrides Sub OnKeyDown (kevent As KeyEventArgs)

Parameters

kevent
KeyEventArgs

A KeyEventArgs that contains the event data.

Remarks

Raising an event invokes the event handler through a delegate. For more information, see Handling and Raising Events.

The OnKeyDown 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.

Note

Do not call OnKeyDown if the button is disabled (this includes calls to the base class's OnKeyDown method when you override OnKeyDown in a derived class). When disabling the button in an override of OnKeyDown, call the base class's OnKeyDown method before disabling the button, or do not call it at all.

Notes to Inheritors

When overriding OnKeyDown(KeyEventArgs) in a derived class, be sure to call the base class's OnKeyDown(KeyEventArgs) method so that registered delegates receive the event.

Applies to

See also