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Control.KeyUp Event

Occurs when a key is released while the control has focus.

[Visual Basic]
Public Event KeyUp As KeyEventHandler
[C#]
public event KeyEventHandler KeyUp;
[C++]
public: __event KeyEventHandler* KeyUp;

[JScript] In JScript, you can handle the events defined by a class, but you cannot define your own.

Event Data

The event handler receives an argument of type KeyEventArgs containing data related to this event. The following KeyEventArgs properties provide information specific to this event.

Property Description
Alt Gets a value indicating whether the ALT key was pressed.
Control Gets a value indicating whether the CTRL key was pressed.
Handled Gets or sets a value indicating whether the event was handled.
KeyCode Gets the keyboard code for a KeyDown or KeyUp event.
KeyData Gets the key data for a KeyDown or KeyUp event.
KeyValue Gets the keyboard value for a KeyDown or KeyUp event.
Modifiers Gets the modifier flags for a KeyDown or KeyUp event. This indicates which combination of modifier keys (CTRL, SHIFT, and ALT) were pressed.
Shift Gets a value indicating whether the SHIFT key was pressed.

Remarks

Key events occur in the following order:

  1. KeyDown
  2. KeyPress
  3. KeyUp

To handle keyboard events only at the form level and not allow other controls to receive keyboard events, set the KeyPressEventArgs.Handled property in your form's KeyPress event-handling method to true. Certain keys, such as the TAB, RETURN, ESCAPE, and arrow keys are handled by controls automatically. In order to have these keys raise the KeyUp event, you must override the IsInputKey method in each control on your form. The code for the override of IsInputKey would need to determine if one of the special keys is pressed and return a value of true.

For more information about handling events, see Consuming Events.

.NET Compact Framework Platform Note:  In addtion to the base Control class, the .NET Compact Framework provides support for this event on controls with Service Pack 2 and later. The Smart Devices Developer Community Web site provides information about the availability of service packs, see http://go.microsoft.com/fwlink/?LinkId=16561.

Example

[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 handling 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 handling 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));
    }
}

[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 handling 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, S"Enter your first name",
         Point(textBox1->Right, this->textBox1->Bottom));
   }
}

[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button Language Filter in the upper-left corner of the page.

Requirements

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family

See Also

Control Class | Control Members | System.Windows.Forms Namespace | OnKeyUp

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