#624 – Information Available to Key Up/Down Events

All four of the keypress-related events (PreviewKeyDown, KeyDown, PreviewKeyUp, and KeyUp) send an instance of the KeyEventArgs object to the associated event handler.

private void TextBox_KeyDown(object sender, KeyEventArgs e)
{
}

Here are some of the more important properties available in the KeyEventArgs object:

• Key property – The System.Windows.Input.Key being pressed.  E.g. Key.Q
• Timestamp – Time of key press, in # ticks (milliseconds) since last reboot
• IsDown / IsUp – Is the key currently down or up?
• IsRepeat – Is this keystroke a repeat due to holding a key down?
• IsToggled – For keys that toggle, like Caps Lock, indicates current toggled state
• Source – The control that had focus when the key was pressed
• OriginalSource – Either the control where the key was pressed, or a lower-level child element
• Handled – Can set to true to indicate that you’ve handled the event, short-circuiting the event routing (generally)