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UIElement.PreviewKeyDown Event

Definition

Occurs when a key is pressed while focus is on this element.

public:
 virtual event System::Windows::Input::KeyEventHandler ^ PreviewKeyDown;
public event System.Windows.Input.KeyEventHandler PreviewKeyDown;
member this.PreviewKeyDown : System.Windows.Input.KeyEventHandler 
Public Custom Event PreviewKeyDown As KeyEventHandler 

Event Type

Implements

Remarks

Key handling interacts with other platform features such as commanding and text composition. The KeyDown event is a lower-level text input event that might not behave as expected on certain controls. This is because some controls have control compositing or class handling that provides a higher-level version of text input handling and related events.

This event creates an alias for the Keyboard.PreviewKeyDown attached event for this class, so that PreviewKeyDown is part of the class members list when UIElement is inherited as a base element. Event handlers that are attached to the PreviewKeyDown event are attached to the underlying Keyboard.PreviewKeyDown attached event and receive the same event data instance.

Routed Event Information

Identifier field PreviewKeyDownEvent
Routing strategy Tunneling
Delegate KeyEventHandler
  • The corresponding bubbling event is KeyDown.

  • Override OnPreviewKeyDown to implement class handling for this event in derived classes.

Applies to

See also