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Classe KeyEventArgs

Provides data for the KeyUp and KeyDown events.

Spazio dei nomi: System.Windows.Input
Assembly: PresentationCore (in presentationcore.dll)
Spazio dei nomi XML:  http://schemas.microsoft.com/winfx/2006/xaml/presentation

public class KeyEventArgs : KeyboardEventArgs
public class KeyEventArgs extends KeyboardEventArgs
public class KeyEventArgs extends KeyboardEventArgs
Non è possibile utilizzare questa classe gestita in XAML.

KeyEventArgs is used with the following events: KeyUp, KeyDown, and the corresponding tunneling events.

A key can be in both the up and toggled states or the down and toggled states. For this reason, determining whether a key is up or down is not as simple as checking the KeyStates value as a numeric value. Instead, you should check the value by treating it as a flag enumeration. Use an AND comparison of the first bit. Alternatively, use the helper properties IsUp, IsDown, and IsToggled to determine whether a given key is up, down, or toggled.

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

I membri statici pubblici (Shared in Visual Basic) di questo tipo sono validi per le operazioni multithreading. I membri di istanza non sono garantiti come thread safe.

Microsoft .NET Framework 3.0 è supportato in Windows Vista, Microsoft Windows XP SP2 e Windows Server 2003 SP1.

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