Control Methods


.NET Framework Class Library
Control..::.OnKeyUp Method

Raises the KeyUp event.

Namespace:  System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)
Syntax

Visual Basic (Declaration)
Protected Overridable Sub OnKeyUp ( _
    e As KeyEventArgs _
)
Visual Basic (Usage)
Dim e As KeyEventArgs

Me.OnKeyUp(e)
C#
protected virtual void OnKeyUp(
    KeyEventArgs e
)
Visual C++
protected:
virtual void OnKeyUp(
    KeyEventArgs^ e
)
JScript
protected function OnKeyUp(
    e : KeyEventArgs
)

Parameters

e
Type: System.Windows.Forms..::.KeyEventArgs
A KeyEventArgs that contains the event data.
Remarks

Raising an event invokes the event handler through a delegate. For more information, see Raising an Event.

The OnKeyUp 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.

Notes to Inheritors:

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

Examples

The following code example uses the KeyUp event with the Help class to display pop-up style help to the user.

Visual Basic
' 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 'textBox1_KeyUp
C#
// 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));
    }
}
Visual C++
   // 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) );
      }
   }
Platforms

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
Version Information

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0
See Also

Reference

Tags : control


Page view tracker