KBDLLHOOKSTRUCT

The KBDLLHOOKSTRUCT structure contains information about a low-level keyboard input event.

typedef struct tagKBDLLHOOKSTRUCT {
    DWORD vkCode;      // virtual key code
    DWORD scanCode;    // scan code
    DWORD flags;       // flags
    DWORD time;        // time stamp for this message
    DWORD dwExtraInfo; // extra info from the driver or keybd_event
} KBDLLHOOKSTRUCT, FAR *LPKBDLLHOOKSTRUCT, *PKBDLLHOOKSTRUCT;
 

Members

vkCode

Specifies a virtual-key code. The code must be a value in the range 1 to 254.

scanCode

Specifies a hardware scan code for the key.

flags

Specifies the extended-key flag, event-injected flag, context code, and transition-state flag.

Value	Description
0	Specifies whether the key is an extended key, such as a function key or a key on the numeric keypad. The value is 1 if the key is an extended key; otherwise, it is 0.
1-3	Reserved.
4	Specifies whether the event was injected. The value is 1 if the event was injected; otherwise, it is 0.
5	Specifies the context code. The value is 1 if the ALT key is pressed; otherwise, it is 0.
6	Reserved.
7	Specifies the transition state. The value is 0 if the key is pressed and 1 if it is being released.

An application can use the following values to test the keystroke flags:

Value	Purpose
LLKHF_EXTENDED	Test the extended-key flag.
LLKHF_INJECTED	Test the event-injected flag.
LLKHF_ALTDOWN	Test the context code.
LLKHF_UP	Test the transition-state flag.

time

Specifies the time stamp for this message.

dwExtraInfo

Specifies extra information associated with the message.

QuickInfo

  Windows NT: Requires version 4.0 SP3 or later.
  Windows: Unsupported.
  Windows CE: Unsupported.
  Header: Declared in winuser.h.

See Also

Hooks Overview, Hook Structures, LowLevelKeyboardProc, SetWindowsHookEx