keys

enum class xtd::forms::keys : long long

strong

Specifies key codes and modifiers.

Header

#include <xtd/forms/keys>

Namespace

xtd::forms

Library

xtd.forms

Remarks

The keys class contains constants for processing keyboard input. The members of the keys enumeration consist of a key code and a set of modifiers combined into a single integer value. In the Win32 application programming interface (API) a key value has two halves, with the high-order bits containing the key code (which is the same as a Windows virtual key code), and the low-order bits representing key modifiers such as the SHIFT, CONTROL, and ALT keys.

Warning

Do not use the values in this enumeration for combined bitwise operations. The values in the enumeration are not mutually exclusive.

Note

This enumeration provides no way to test whether the CAPS LOCK or NUM LOCK keys are currently activated. You can use one of the following techniques to determine if these keys are activated:

• Call the IsKeyLocked method of the Control class.
• For finer control, use the Win32 API functions GetKeyState, GetAsyncKeyState, or GetKeyboardState defined in user32.dll, to do this. For more information about calling native functions, see Consuming Unmanaged DLL Functions.

Remarks

The following table shows the key code values represented by two enumerated values, representing both the general original equipment manufacturer (OEM) keys and the more specific U.S.-keyboard associations.

Hexadecimal value	U.S. keyboard	General OEM
BA	oem_semicolon	oem1
BF	oem_question	oem2
C0	oem_tilde	oem3
DB	oem_open_brackets	oem4
DC	oem_pipe	oem5
DD	oem_close_brackets	oem6
DE	oem_quotes	oem7
E2	oem_backslash	oem102

On Apple platforms, references to xtd::forms::keys::control_key and xtd::forms::keys::control correspond to the command keys on the Macintosh keyboard, and references to xtd::forms::keys::lwin, xtd::forms::keys::rwin and xtd::forms::keys::meta correspond to the control keys. In effect, developers can use the same shortcut descriptions across all platforms, and their applications will automatically work as expected on Apple platforms.

Examples

The following code example uses the KeyDown event to determine the type of character entered into the control.

// bool flag used to determine when a character other than a number is entered.
bool non_number_entered = false;
 
// Handle the KeyDown event to determine the type of character entered into the control.
void text_box1_key_down(object& sender, key_event_args& e) {
  // Initialize the flag to false.
  non_number_entered = false;
 
  // Determine whether the keystroke is a number from the top of the keyboard.
  if (e.key_code() < keys::d0 || e.key_code() > keys::d9) {
    // Determine whether the keystroke is a number from the keypad.
    if (e.key_code() < keys::num_pad0 || e.key_code() > keys::num_pad9) {
      // Determine whether the keystroke is a backspace.
      if(e.key_code() != keys::back) {
        // A non-numerical keystroke was pressed.
        // Set the flag to true and evaluate in xtd::forms::control::key_press event.
        non_number_entered = true;
      }
    }
  }
  //If shift key was pressed, it's not a number.
  if (control::modifier_keys() == keys::Shift) {
    non_number_entered = true;
  }
}
 
// This event occurs after the KeyDown event and can be used to prevent
// characters from entering the control.
void text_box1_key_press(object& sender, xtd::forms::key_press_event_args& e) {
  // Check for the flag being set in the xtd::forms::control::key_down event.
  if (non_number_entered == true) {
    // Stop the character from being entered into the control since it is non-numerical.
    e.handled(true);
  }
}

Enumerator
none	No key pressed.
lbutton	The left mouse button.
rbutton	The right mouse button.
cancel	The CANCEL key.
mbutton	The middle mouse button (three-button mouse).
xbutton1	The first x mouse button (five-button mouse).
xbutton2	The second x mouse button (five-button mouse).
back	The BACK key.
tab	The TAB key.
line_feed	The LINEFEED key.
clear	The CLEAR key.
enter	The ENTER key.
ret	The RETURN key.
shift_key	The SHIFT key.
control_key	The CTRL key.
menu	The ALT key.
pause	The PAUSE key.
caps_lock	The CAPS LOCK key.
capital	The CAPS LOCK key.
kana_mode	The IME Kana mode key.
hanguel_mode	The IME Hanguel mode key. (maintained for compatibility; use HangulMode)
hangul_mode	The IME Hangul mode key.
junja_mode	The IME Junja mode key.
final_mode	The IME Final mode key.
kanji_mode	The IME Kanji mode key.
hanja_mode	The IME Hanja mode key.
escape	The ESC key.
ime_convert	The IME convert key.
ime_nonconvert	The IME nonconvert key.
ime_accept	The IME accept key.
ime_mode_change	The IME mode change key.
space	The SPACEBAR key.
page_up	The PAGE UP key.
prior	The PAGE UP key.
page_down	The PAGE DOWN key.
next	The PAGE DOWN key.
end	The END key.
home	The HOME key.
left	The LEFT key.
up	The UP key.
right	The RIGHT key.
down	The DOWN key.
select	The SELECT key.
print	The PRINT key.
execute	The EXECUTE key.
print_screen	The PRINT SCREEN key.
snapshot	The PRINT SCREEN key.
insert	The INSERT key.
del	The DEL key.
help	The HELP key.
d0	The 0 key.
d1	The 1 key.
d2	The 2 key.
d3	The 3 key.
d4	The 4 key.
d5	The 5 key.
d6	The 6 key.
d7	The 7 key.
d8	The 8 key.
d9	The 9 key.
a	The A key.
b	The B key.
c	The C key.
d	The D key.
e	The E key.
f	The F key.
g	The G key.
h	The H key.
i	The I key.
j	The J key.
k	The K key.
l	The L key.
m	The M key.
n	The N key.
o	The O key.
p	The P key.
q	The Q key.
r	The R key.
s	The S key.
t	The T key.
u	The U key.
v	The V key.
w	The W key.
x	The X key.
y	The Y key.
z	The Z key.
lwin	The left Windows logo key (Microsoft Natural Keyboard).
rwin	The right Windows logo key (Microsoft Natural Keyboard).
apps	The application key (Microsoft Natural Keyboard).
sleep	The computer sleep key.
num_pad0	The 0 key on the numeric keypad.
num_pad1	The 1 key on the numeric keypad.
num_pad2	The 2 key on the numeric keypad.
num_pad3	The 3 key on the numeric keypad.
num_pad4	The 4 key on the numeric keypad.
num_pad5	The 5 key on the numeric keypad.
num_pad6	The 6 key on the numeric keypad.
num_pad7	The 7 key on the numeric keypad.
num_pad8	The 8 key on the numeric keypad.
num_pad9	The 9 key on the numeric keypad.
multiply	The multiply key.
add	The add key.
separator	The separator key.
subtract	The subtract key.
decimal	The decimal key.
divide	The divide key.
f1	The F1 key.
f2	The F2 key.
f3	The F3 key.
f4	The F4 key.
f5	The F5 key.
f6	The F6 key.
f7	The F7 key.
f8	The F8 key.
f9	The F9 key.
f10	The F10 key.
f11	The F11 key.
f12	The F12 key.
f13	The F13 key.
f14	The F14 key.
f15	The F15 key.
f16	The F16 key.
f17	The F17 key.
f18	The F18 key.
f19	The F19 key.
f20	The F20 key.
f21	The F21 key.
f22	The F22 key.
f23	The F23 key.
f24	The F24 key.
num_lock	The NUM LOCK key.
scroll	The SCROLL LOCK key.
lshift_key	The left SHIFT key.
rshift_key	The right SHIFT key.
lcontrol_key	The left CTRL key.
rcontrol_key	The right CTRL key.
lmenu	The left ALT key.
rmenu	The right ALT key.
browser_back	The browser back key.
browser_forward	The browser forward key.
browser_refresh	The browser refresh key.
browser_stop	The browser stop key.
browser_search	The browser search key.
browser_favorites	The browser favorites key.
browser_home	The browser home key.
volume_mute	The volume mute key.
volume_down	The volume down key.
volume_up	The volume up key.
media_next_track	The media next track key.
media_previous_track	The media previous track key.
media_stop	The media stop key.
media_play_pause	The media play pause key.
launch_mail	The launch mail key.
select_media	The select media key.
launch_application1	The start application one key.
launch_application2	The start application two key.
oem_semicolon	The OEM Semicolon key on a US standard keyboard.
oem1	The OEM 1 key.
oem_plus	The OEM plus key on any country/region keyboard.
oem_comma	The OEM comma key on any country/region keyboard.
oem_minus	The OEM minus key on any country/region keyboard.
oem_period	The OEM period key on any country/region keyboard.
oem_question	The OEM question mark key on a US standard keyboard.
oem2	The OEM 2 key.
oem_tilde	The OEM tilde key on a US standard keyboard.
oem3	The OEM 3 key.
oem_open_brackets	The OEM open bracket key on a US standard keyboard.
oem4	The OEM 4 key.
oem_pipe	The OEM pipe key on a US standard keyboard.
oem5	The OEM 5 key.
oem_close_brackets	The OEM close bracket key on a US standard keyboard.
oem6	The OEM 6 key.
oem_quotes	The OEM singled/double quote key on a US standard keyboard.
oem7	The OEM 7 key.
oem8	The OEM 8 key.
oem_backslash	The OEM angle bracket or backslash key on the RT 102 key keyboard.
oem102	The OEM 102 key.
process_key	The PROCESS KEY key.
packet	Used to pass Unicode characters as if they were keystrokes. The Packet key value is the low word of a 32-bit virtual-key value used for non-keyboard input methods.
attn	The ATTN key.
crsel	The CRSEL key.
exsel	The EXSEL key.
erase_eof	The ERASE EOF key.
play	The PLAY key.
zoom	The ZOOM key.
no_name	A constant reserved for future use.
pa1	The PA1 key.
oem_clear	The CLEAR key.
command_key	The CMD key.
lcommand_key	The left CMD key.
rcommand_key	The right CMD key.
function_key	The FUNCTION key.
shift	The SHIFt modifier key.
control	The CTRL modifier key. Remarks On macOS, the xtd::forms::keys::control modifier value corresponds to the command keys on the keyboard, and the xtd::forms::keys::meta modifier value corresponds to the control keys.
command	The CMD modifier key. Remarks The Apple keyboard xtd::forms::keys::command modifier key corresponding to the xtd::forms::keys::control modifier key.
alt	The ALT modifier key.
option	The OPT modifier key. Remarks The Apple keyboard xtd::forms::keys::option modifier key corresponding to the xtd::forms::keys::alt modifier key.
meta	The METTA modifier key. Remarks OnWindows and Linux, the xtd::forms::keys::meta modifier value corresponds to the Windows Left or Right keys. On macOS, the xtd::forms::keys::control modifier value corresponds to the command keys on the keyboard, and the xtd::forms::keys::meta modifier value corresponds to the control keys.
function	The FUNCTION modifier key.
key_code	The bitmask to extract a key code from a key value.
modifiers	The bitmask to extract modifiers from a key value.