Control.KeyUp Ereignis
Definition
Wichtig
Einige Informationen beziehen sich auf Vorabversionen, die vor dem Release ggf. grundlegend überarbeitet werden. Microsoft übernimmt hinsichtlich der hier bereitgestellten Informationen keine Gewährleistungen, seien sie ausdrücklich oder konkludent.
Tritt auf, wenn eine Taste losgelassen wird, während das Steuerelement den Fokus hat.
public:
event System::Windows::Forms::KeyEventHandler ^ KeyUp;public event System.Windows.Forms.KeyEventHandler KeyUp;public event System.Windows.Forms.KeyEventHandler? KeyUp;member this.KeyUp : System.Windows.Forms.KeyEventHandler Public Custom Event KeyUp As KeyEventHandler Ereignistyp
Beispiele
Im folgenden Codebeispiel wird das KeyUp Ereignis mit der Help Klasse zum Anzeigen der Popupformatvorlage für den Benutzer verwendet.
// This example demonstrates how to use the KeyUp event with the Help class to display
// pop-up style help to the user of the application. When the user presses F1, the Help
// class displays a pop-up window, similar to a ToolTip, near the control. This example assumes
// that a TextBox control, named textBox1, has been added to the form and its KeyUp
// event has been connected to this event handler method.
private:
void textBox1_KeyUp( Object^ /*sender*/, System::Windows::Forms::KeyEventArgs^ e )
{
// Determine whether the key entered is the F1 key. Display help if it is.
if ( e->KeyCode == Keys::F1 )
{
// Display a pop-up help topic to assist the user.
Help::ShowPopup( textBox1, "Enter your first name", Point(textBox1->Right,this->textBox1->Bottom) );
}
}
// This example demonstrates how to use the KeyUp event with the Help class to display
// pop-up style help to the user of the application. When the user presses F1, the Help
// class displays a pop-up window, similar to a ToolTip, near the control. This example assumes
// that a TextBox control, named textBox1, has been added to the form and its KeyUp
// event has been contected to this event handler method.
private void textBox1_KeyUp(object sender, System.Windows.Forms.KeyEventArgs e)
{
// Determine whether the key entered is the F1 key. Display help if it is.
if(e.KeyCode == Keys.F1)
{
// Display a pop-up help topic to assist the user.
Help.ShowPopup(textBox1, "Enter your first name", new Point(textBox1.Right, this.textBox1.Bottom));
}
}
' This example demonstrates how to use the KeyUp event with the Help class to display
' pop-up style help to the user of the application. When the user presses F1, the Help
' class displays a pop-up window, similar to a ToolTip, near the control. This example assumes
' that a TextBox control, named textBox1, has been added to the form and its KeyUp
' event has been contected to this event handler method.
Private Sub textBox1_KeyUp(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles textBox1.KeyUp
' Determine whether the key entered is the F1 key. Display help if it is.
If e.KeyCode = Keys.F1 Then
' Display a pop-up help topic to assist the user.
Help.ShowPopup(textBox1, "Enter your first name", New Point(textBox1.Right, Me.textBox1.Bottom))
End If
End Sub
Im folgenden Codebeispiel wird die Reihenfolge des Aufsteigens der KeyDownEreignisse KeyUp und KeyPress ereignisse veranschaulicht, wie Ereignishandler für sie registriert werden.
public partial class Form2 : Form
{
public Form2()
{
InitializeComponent();
textBox2.Multiline = true;
textBox2.ScrollBars = ScrollBars.Both;
//Setup events that listens on keypress
textBox1.KeyDown += TextBox1_KeyDown;
textBox1.KeyPress += TextBox1_KeyPress;
textBox1.KeyUp += TextBox1_KeyUp;
}
// Handle the KeyUp event to print the type of character entered into the control.
private void TextBox1_KeyUp(object sender, KeyEventArgs e)
{
textBox2.AppendText( $"KeyUp code: {e.KeyCode}, value: {e.KeyValue}, modifiers: {e.Modifiers}" + "\r\n");
}
// Handle the KeyPress event to print the type of character entered into the control.
private void TextBox1_KeyPress(object sender, KeyPressEventArgs e)
{
textBox2.AppendText( $"KeyPress keychar: {e.KeyChar}" + "\r\n");
}
// Handle the KeyDown event to print the type of character entered into the control.
private void TextBox1_KeyDown(object sender, KeyEventArgs e)
{
textBox2.AppendText( $"KeyDown code: {e.KeyCode}, value: {e.KeyValue}, modifiers: {e.Modifiers}" + "\r\n");
}
}
Public Class Form2
' Handle the KeyDown event to print the type of character entered into the control.
Private Sub TextBox1_KeyDown(sender As Object, e As KeyEventArgs) Handles TextBox1.KeyDown
TextBox2.AppendText($"KeyDown code: {e.KeyCode}, value: {e.KeyValue}, modifiers: {e.Modifiers}" + vbCrLf)
End Sub
' Handle the KeyPress event to print the type of character entered into the control.
Private Sub TextBox1_KeyPress(sender As Object, e As KeyPressEventArgs) Handles TextBox1.KeyPress
TextBox2.AppendText($"KeyPress keychar: {e.KeyChar}" + vbCrLf)
End Sub
' Handle the KeyUp event to print the type of character entered into the control.
Private Sub TextBox1_KeyUp(sender As Object, e As KeyEventArgs) Handles TextBox1.KeyUp
TextBox2.AppendText($"KeyUp code: {e.KeyCode}, value: {e.KeyValue}, modifiers: {e.Modifiers}" + vbCrLf)
End Sub
End Class
Hinweise
Wichtige Ereignisse treten in der folgenden Reihenfolge auf:
Wenn Sie Tastaturereignisse nur auf Formularebene behandeln und keine anderen Steuerelemente zum Empfangen von Tastaturereignissen aktivieren möchten, legen Sie die Eigenschaft in der KeyPressEventArgs.Handled Ereignisbehandlungsmethode Ihres Formulars KeyPress auf true. Bestimmte Tasten wie TAB, EINGABETASTE, ESC und Pfeiltasten werden automatisch von Steuerelementen behandelt. Damit diese Schlüssel das KeyUp Ereignis auslösen, müssen Sie die IsInputKey Methode in jedem Steuerelement in Ihrem Formular überschreiben. Der Code für die Außerkraftsetzung muss IsInputKey ermitteln, ob eine der Spezialtasten gedrückt wird, und einen Wert von true.
Weitere Informationen zur Behandlung von Ereignissen finden Sie unter behandeln und Auslösen von Ereignissen.
