WinGetKeyState: Difference between revisions

Latest revision as of 20:15, 12 April 2024

This function returns the state of the key at the time that the last message obtained from the queue was posted.

Syntax

WinGetKeyState(hwndDeskTop, vkey)

Parameters

hwndDeskTop (HWND) - input

Desktop-window handle.

HWND_DESKTOP - The desktop-window handle

Other - Specified desktop-window handle.

vkey (LONG) - input: Virtual key value.; Contains the virtual key value in the low-order byte, and zero in the high-order byte. See remarks for possible values.

Returns

lKeyState (LONG) - returns

Key state.

This value is the OR combination of the following bits:

0x0001 - The key has been pressed an odd number of times since the system has been started.

0x8000 - The key is down.

Remarks

See also the WinGetPhysKeyState function. This function is used to determine whether a virtual key is up, down, or toggled.

This function can be used to obtain the state of the pointing device buttons with the VK_BUTTON1, VK_BUTTON2, and VK_BUTTON3 virtual key codes. The following are the possible values for the vkey parameter:

VK_BUTTON1
VK_BUTTON2
VK_BUTTON3

VK_ALT
VK_ALTGRAF
VK_CTRL
VK_SHIFT
VK_SPACE
VK_BACKSPACE
VK_TAB
VK_BACKTAB

VK_BREAK
VK_PAUSE
VK_NEWLINE

VK_END
VK_HOME
VK_LEFT
VK_UP
VK_DOWN
VK_RIGHT
VK_PAGEDOWN
VK_PAGEUP
VK_DELETE
VK_INSERT

VK_CAPSLOCK
VK_NUMLOCK
VK_SCRLLOCK
VK_PRINTSCRN
VK_ENTER
VK_ESC
VK_SYSRO

VK_ENDDRAG
VK_CLEAR
VK_EREOF
VK_PA1
VK_ATTN
VK_CRSEL
VK_EXCEL
VK_COPY
VK_BLK1
VK_BLK2
VK_MENU

VK_BIDI_FIRST
VK_BIDI_LAST
VK_DBCSFIRST
VK_DBCSLAST
VK_USERFIRST
VK_USERLAST

VK_F1
VK_F2
VK_F3
VK_F4
VK_F5
VK_F6
VK_F7
VK_F8
VK_F9
VK_F10
VK_F11
VK_F12
VK_F13
VK_F14
VK_F15
VK_F16
VK_F17
VK_F18
VK_F19
VK_F20
VK_F21
VK_F22
VK_F23
VK_F24

Errors

Possible returns from WinGetLastError

PMERR_INVALID_HWND (0x1001): An invalid window handle was specified.

Example Code

This example uses WinGetKeyState to check if mouse button 1 was depressed when a WM_TIMER message was received. A high-pitched beep is emitted if it was depressed, and a low-pitched beep if it was not.

#define INCL_WININPUT /* Window Input functions */
#define INCL_DOSPROCESS /* OS/2 Process functions */
#include <os2.h>

LONG lKeyState; /* Key state */
LONG vkey; /* Virtual key value */

case WM_TIMER:
    /* Get the key state of mouse button 1 */
    vkey = VK_BUTTON1;
    lKeyState = WinGetKeyState(HWND_DESKTOP, vkey);
    
    /* Emit a high pitched beep if mouse button 1 is depressed */
    /* when the timer message occurred; otherwise, emit a low */
    /* pitched beep */
    if (lKeyState & 0x8000)
        DosBeep(1000,100L);
    else
        DosBeep(200,100L);

Related Functions

WinEnablePhysInput
WinFocusChange
WinGetPhysKeyState
WinQueryFocus
WinSetFocus
WinSetKeyboardStateTable

@@ Line 1: / Line 1: @@
 This function returns the state of the key at the time that the last message obtained from the queue was posted.
-===Syntax===
- WinGetKeyState(hwndDeskTop, vkey);
-===Parameters===
-; hwndDeskTop (HWND) - input
-: Desktop-window handle.
-:: HWND_DESKTOP
-::: The desktop-window handle
-:: Other
-::: Specified desktop-window handle.
-; vkey (LONG) - input
+==Syntax==
-: Virtual key value.
+ WinGetKeyState(hwndDeskTop, vkey)
-: Contains the virtual key value in the low-order byte, and zero in the high-order byte. See remarks for possible values.
-===Return Value===
+==Parameters==
-; lKeyState (LONG) - returns
+;hwndDeskTop (HWND) - input: Desktop-window handle.
-: Key state.
+:: HWND_DESKTOP - The desktop-window handle
+:: Other - Specified desktop-window handle.
+;vkey (LONG) - input: Virtual key value.
+:Contains the virtual key value in the low-order byte, and zero in the high-order byte. See remarks for possible values.
+==Returns==
+; lKeyState (LONG) - returns: Key state.
 : This value is the OR combination of the following bits:
-:: 0x0001
+:: 0x0001 - The key has been pressed an odd number of times since the system has been started.
-::: The key has been pressed an odd number of times since the system has been started.
+:: 0x8000 - The key is down.
-:: 0x8000
-::: The key is down.
-===Remarks===
+==Remarks==
 See also the WinGetPhysKeyState function. This function is used to determine whether a virtual key is up, down, or toggled.
 This function can be used to obtain the state of the pointing device buttons with the VK_BUTTON1, VK_BUTTON2, and VK_BUTTON3 virtual key codes. The following are the possible values for the vkey parameter:
 <PRE>
 VK_BUTTON1
@@ Line 111: / Line 105: @@
 ===Errors===
 Possible returns from WinGetLastError
-; PMERR_INVALID_HWND (0x1001)
+; PMERR_INVALID_HWND (0x1001): An invalid window handle was specified.
-: An invalid window handle was specified.
 ===Example Code===
-This example uses WinGetKeyState to check if mouse button 1 was depressed when a WM_TIMER message was received. A high pitched beep is emitted if it was depressed, and a low pitched beep if it was not.
+This example uses WinGetKeyState to check if mouse button 1 was depressed when a WM_TIMER message was received. A high-pitched beep is emitted if it was depressed, and a low-pitched beep if it was not.
 <pre>
 #define INCL_WININPUT /* Window Input functions */
@@ Line 138: / Line 130: @@
          DosBeep(200,100L);
 </pre>
-Definition
-<PRE>
-#define INCL_WININPUT /* Or use INCL_WIN, INCL_PM, */
-#include <os2.h>
-HWND    hwndDeskTop;  /*  Desktop-window handle. */
-LONG    vkey;         /*  Virtual key value. */
-LONG    lKeyState;    /*  Key state. */
-lKeyState = WinGetKeyState(hwndDeskTop, vkey);
-</PRE>
 ===Related Functions===
@@ Line 157: / Line 138: @@
 * WinSetFocus
 * WinSetKeyboardStateTable
+[[Category:Win]]