| Platform SDK: DirectX |
This section covers the identification of keys for which data is reported by the IDirectInputDevice7::GetDeviceState and IDirectInputDevice7::GetDeviceData methods. For more information on interpreting the data from GetDeviceData, see Time Stamps and Sequence Numbers.
This section covers the identification of keys for which data is reported by the DirectInputDevice.GetDeviceState and DirectInputDevice.GetDeviceData methods. For more information on interpreting the data from GetDeviceData, see Time Stamps and Sequence Numbers.
In one important respect, DirectInput differs from other ways of reading the keyboard in Windows. Keyboard data refers not to virtual keys but to the actual physical keys—that is, the scan codes. DIK_ENTER, for example, refers to the ENTER key on the main keyboard, but not to the one on the numerical keypad.
DirectInput defines a constant for each key on the enhanced keyboard, as well as the additional keys found on international keyboards. Because NEC keyboards support different scan codes than the PC-enhanced keyboards, DirectInput translates NEC key scan codes into PC-enhanced scan codes where possible.
Not all PC-enhanced keyboards have the Windows keys (DIK_LWIN, DIK_RWIN, and DIK_APPS). There is no way to determine whether the keys are physically available.
Laptops and other small computers often do not implement a full set of keys. Instead, some keys (typically numeric keypad keys) are multiplexed with other keys, selected by an auxiliary mode key, which does not generate a separate scan code.
If the keyboard subtype indicates a PC XT or PC AT keyboard, the following keys are not available: DIK_F11, DIK_F12, and all the extended keys (DIK_* values greater than 0x7F). Furthermore, the PC XT keyboard lacks DIK_SYSRQ.
Japanese keyboards, particularly the NEC PC-98 keyboards, contain a substantially different set of keys than U.S. keyboards. For more information, see DirectInput and Japanese Keyboards.