alt key

Puedes utilizar esta función

SHORT GetKeyState(
int nVirtKey // virtual-key code
);

la función GetKeyState recupera el estado de la tecla virtual especifica. El
estado especifica cuando la tecla esta sin pulsar, pulsadaa, o mantenida.

Naturalmente como puedes ver el parametro que dbes pasar a la función es l
tecla

virtual:

VK_CONTROL

VK_SHIFT

VK_MENU

VK_LCONTROL

VK_LSHIFT

VK_LMENU

VK_RCONTROL

VK_RSHIFT

VK_RMENU

El valor devuelto es el estado.

Espero que te sirva.

Animo y sigue aprendiendo

Un saludo a todos los de este grupo(foro)

Se me olvidaba para tecla "ALT"
este es el virtual code:
VK_MENU

De nuevo saludos a todos.

" Paco Garcia" escribía:

Hola

Estoy haciendo un programa en el que un control acepta teclas como VK_LEFT,
VK_RIGHT etc para moverse en una ventana y quería contemplar la posibilidad
de que si pulso ALT + VK_RETURN hiciera algo específico.

¿como averiguo que esta pulsada la tecla ALT?

Gracias

No averiguas.

Pones la combinación en una tabla de aceleradores y dejas que el
handler que corresponda (típicamente, TranslateAccelerator()), genere
un WM_COMMAND.

VK_RETURN CommandId, VIRTKEY, ALT

Hernán

Gracias a todos

Por lo que he averiguado parece ser que la pulsación de ALT se controla en
el mensaje WM_SYSKEYDOWN

Saludos y gracias

MSDN:

WM_SYSKEYDOWN Notification

-
-

The WM_SYSKEYDOWN message is posted to the window with the keyboard focus
when the user presses the F10 key (which activates the menu bar) or holds
down the ALT key and then presses another key. It also occurs when no window
currently has the keyboard focus; in this case, the WM_SYSKEYDOWN message is
sent to the active window. The window that receives the message can
distinguish between these two contexts by checking the context code in the
lParam parameter.

Syntax

WM_SYSKEYDOWN

WPARAM wParam
LPARAM lParam;
Parameters

wParam
Specifies the virtual-key code of the key being pressed.
lParam
Specifies the repeat count, scan code, extended-key flag, context code,
previous key-state flag, and transition-state flag, as shown in the
following table.
0-15
Specifies the repeat count for the current message. The value is the
number of times the keystroke is autorepeated as a result of the user
holding down the key. If the keystroke is held long enough, multiple
messages are sent. However, the repeat count is not cumulative.
16-23
Specifies the scan code. The value depends on the OEM.
24
Specifies whether the key is an extended key, such as the right-hand
ALT and CTRL keys that appear on an enhanced 101- or 102-key keyboard. The
value is 1 if it is an extended key; otherwise, it is 0.
25-28
Reserved; do not use.
29
Specifies the context code. The value is 1 if the ALT key is down
while the key is pressed; it is 0 if the WM_SYSKEYDOWN message is posted to
the active window because no window has the keyboard focus.
30
Specifies the previous key state. The value is 1 if the key is down
before the message is sent, or it is 0 if the key is up.
31
Specifies the transition state. The value is always 0 for a
WM_SYSKEYDOWN message.
Return Value

An application should return zero if it processes this message.




Remarks

The DefWindowProc function examines the specified key and generates a
WM_SYSCOMMAND message if the key is either TAB or ENTER.

When the context code is zero, the message can be passed to the
TranslateAccelerator function, which will handle it as though it were a
normal key message instead of a character-key message. This allows
accelerator keys to be used with the active window even if the active window
does not have the keyboard focus.

Because of automatic repeat, more than one WM_SYSKEYDOWN message may occur
before a WM_SYSKEYUP message is sent. The previous key state (bit 30) can be
used to determine whether the WM_SYSKEYDOWN message indicates the first down
transition or a repeated down transition.

For enhanced 101- and 102-key keyboards, enhanced keys are the right ALT
and CTRL keys on the main section of the keyboard; the INS, DEL, HOME, END,
PAGE UP, PAGE DOWN, and arrow keys in the clusters to the left of the
numeric keypad; and the divide (/) and ENTER keys in the numeric keypad.
Other keyboards may support the extended-key bit in the lParam parameter.

This message is also sent whenever the user presses the F10 key without
the ALT key.




" Paco Garcia" escribió en el mensaje
news:e0Rc3aX#

Hola

Estoy haciendo un programa en el que un control acepta teclas como

VK_LEFT,

VK_RIGHT etc para moverse en una ventana y quería contemplar la

posibilidad

de que si pulso ALT + VK_RETURN hiciera algo específico.

¿como averiguo que esta pulsada la tecla ALT?

Gracias