KeyEventArgs.Modifiers-Eigenschaft

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));
    }
}

    // 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.get_KeyCode().Equals(Keys.F1) && (e.get_Alt() || e.get_Control() 
            || e.get_Shift())) {
            // Display a pop-up Help topic to assist the user.
            Help.ShowPopup(textBox1, "Enter your name.", new Point(textBox1.
                get_Bottom(), textBox1.get_Right()));
        }
        else {
            if (e.get_KeyCode().Equals(Keys.F2) && e.get_Modifiers().
                Equals(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.get_Top(), this.textBox1.get_Left()));
            }
        }
    } //textBox1_KeyDown
} //Form1