如何在按钮单击期间确定何时按住控制键

如何在C#Windows程序中单击按钮时确定何时按住控制键？我想为Ctrl/Click执行一个操作,为Click执行另一个操作.

还有一点:

private void button1_Click ( object sender, EventArgs e )
{           
    if( (ModifierKeys  & Keys.Control) == Keys.Control )
    {
        ControlClickMethod();    
    }
    else
    {
        ClickMethod();
    }
}

private void ControlClickMethod()
{
    MessageBox.Show( "Control is pressed" );
}

private void ClickMethod()
{
    MessageBox.Show ( "Control is not pressed" );
}

假设WinForms,使用Control.ModifierKeys,例如:

private void button1_Click(object sender, EventArgs e) {
    MessageBox.Show(Control.ModifierKeys.ToString());
}

假设使用WPF,请使用Keyboard.Modifiers,例如:

private void Button_Click(object sender, RoutedEventArgs e) {
    MessageBox.Show(Keyboard.Modifiers.ToString());
}