Public Event KeyDown As KeyEventHandler

Dim instance As UIElement
Dim handler As KeyEventHandler

AddHandler instance.KeyDown, handler

public event KeyEventHandler KeyDown

public:
virtual  event KeyEventHandler^ KeyDown {
    void add (KeyEventHandler^ value);
    void remove (KeyEventHandler^ value);
}

JScript does not support events.

<object KeyDown="KeyEventHandler" .../>

Implements

• The corresponding tunneling event is PreviewKeyDown.

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

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

This example shows how to detect when the Enter key is pressed on the keyboard.

This example consists of a Extensible Application Markup Language (XAML) file and a code-behind file. For the complete samples, see Keyboard Key Sample.

When the user presses the Enter key in the TextBox, the input in the text box appears in another area of the user interface (UI).

The following XAML creates the user interface, which consists of a StackPanel, a TextBlock, and a TextBox.

<StackPanel>
  <TextBlock Width="300" Height="20">
    Type some text into the TextBox and press the Enter key.
  </TextBlock>
  <TextBox Width="300" Height="30" Name="textBox1"
           KeyDown="OnKeyDownHandler"/>
  <TextBlock Width="300" Height="100" Name="textBlock1"/>
</StackPanel>

The following code behind creates the KeyDown event handler. If the key that is pressed is the Enter key, a message is displayed in the TextBlock.

Private Sub OnKeyDownHandler(ByVal sender As Object, ByVal e As KeyEventArgs)
    If (e.Key = Key.Return) Then
        textBlock1.Text = "You Entered: " + textBox1.Text
    End If
End Sub

private void OnKeyDownHandler(object sender, KeyEventArgs e)
{
    if (e.Key == Key.Return)
    {
        textBlock1.Text = "You Entered: " + textBox1.Text;
    }
}

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003

.NET Framework

Reference

Other Resources