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KeyEventArgs.Control Property

Definition

Gets a value indicating whether the CTRL key was pressed.

public:
 property bool Control { bool get(); };
public bool Control { get; }
member this.Control : bool
Public ReadOnly Property Control As Boolean

Property Value

true if the CTRL key was pressed; otherwise, false.

Examples

The following code example demonstrates how to use the KeyDown event with the Help class to display pop-up style Help to the user of the application. The example uses the KeyEventArgs properties passed to the event handler method to filter for all variations of pressing the F1 key with a modifier key. When the user presses any variation of F1 that includes any keyboard modifier, the Help class displays a pop-up window, similar to a ToolTip, near the control. If the user presses ALT+F2, a different Help pop-up is displayed with additional information.

   // This example demonstrates how to use the KeyDown event with the Help class to display
   // pop-up style help to the user of the application. The example filters for all variations
   // of pressing the F1 key with a modifier key by using the KeyEventArgs properties passed
   // to the event handling method.
   // When the user presses any variation of F1 that includes any keyboard modifier, the Help
   // class displays a pop-up window, similar to a ToolTip, near the control. If the user presses
   // ALT + F2, a different Help pop-up is displayed with additional information. This example assumes
   // that a tTextBox control, named textBox1, has been added to the form and its KeyDown
   // event has been contected to this event handling method.
private:
   void textBox1_KeyDown( Object^ /*sender*/, System::Windows::Forms::KeyEventArgs^ e )
   {
      // Determine whether the key entered is the F1 key. If it is, display Help.
      if ( e->KeyCode == Keys::F1 && (e->Alt || e->Control || e->Shift) )
      {
         
         // Display a pop-up Help topic to assist the user.
         Help::ShowPopup( textBox1, "Enter your name.", Point(textBox1->Bottom,textBox1->Right) );
      }
      else
      if ( e->KeyCode == Keys::F2 && e->Modifiers == Keys::Alt )
      {
         // Display a pop-up Help topic to provide additional assistance to the user.
         Help::ShowPopup( textBox1, "Enter your first name followed by your last name. Middle name is optional.",
            Point(textBox1->Top,this->textBox1->Left) );
      }
   }
private void textBox1_KeyDown(object sender, System.Windows.Forms.KeyEventArgs e)
{
    // Determine whether the key entered is the F1 key. If it is, display Help.
    if(e.KeyCode == Keys.F1 && (e.Alt || e.Control || e.Shift))
    {
        // Display a pop-up Help topic to assist the user.
        Help.ShowPopup(textBox1, "Enter your name.", new Point(textBox1.Bottom, textBox1.Right));
    }
    else if(e.KeyCode == Keys.F2 && e.Modifiers == Keys.Alt)
    {
        // Display a pop-up Help topic to provide additional assistance to the user.
        Help.ShowPopup(textBox1, "Enter your first name followed by your last name. Middle name is optional.",
            new Point(textBox1.Top, this.textBox1.Left));
    }
}
Private Sub textBox1_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles textBox1.KeyDown
    ' Determine whether the key entered is the F1 key. If it is, display Help.
    If e.KeyCode = Keys.F1 AndAlso (e.Alt OrElse e.Control OrElse e.Shift) Then
        ' Display a pop-up Help topic to assist the user.
        Help.ShowPopup(textBox1, "Enter your name.", New Point(textBox1.Bottom, textBox1.Right))
    ElseIf e.KeyCode = Keys.F2 AndAlso e.Modifiers = Keys.Alt Then
        ' Display a pop-up Help topic to provide additional assistance to the user.
        Help.ShowPopup(textBox1, "Enter your first name followed by your last name. Middle name is optional.", _
             New Point(textBox1.Top, Me.textBox1.Left))
    End If
End Sub

Applies to

See also