WM_SYSDEADCHAR
The
WM_SYSDEADCHAR message is sent to the window with the keyboard focus when a
WM_SYSKEYDOWN message is translated by the TranslateMessage function. WM_SYSDEADCHAR
specifies the character code of a system dead key that is, a dead key that is pressed while holding
down the ALT key.
WM_SYSDEADCHAR
chCharCode = (TCHAR) wParam; // character code
lKeyData = lParam;
// key data
Parameters
chCharCode
Value of wParam.
Specifies the character code generated by the system dead key that is, a dead key that is pressed while holding
down the ALT key.
lKeyData
Value of 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:
|
Value |
Description |
|
0-15 |
Specifies
the repeat count. The value is the number of times the keystroke is repeated
as a result of the user holding down the key. |
|
16-23 |
Specifies
the scan code. The value depends on the original equipment manufacturer
(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 held down while the key is pressed;
otherwise, the value is 0. |
|
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 1 if the key is being released, or it is 0
if the key is being pressed. |
Return Values
An
application should return zero if it processes this message.
Remarks
For enhanced
101- and 102-key keyboards, extended 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 lKeyData parameter.
See Also