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KEYBDINPUT structure (winuser.h)

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Contains information about a simulated keyboard event.

Syntax

typedef struct tagKEYBDINPUT {
  WORD      wVk;
  WORD      wScan;
  DWORD     dwFlags;
  DWORD     time;
  ULONG_PTR dwExtraInfo;
} KEYBDINPUT, *PKEYBDINPUT, *LPKEYBDINPUT;

Members

wVk

Type: WORD

A virtual-key code. The code must be a value in the range 1 to 254. If the dwFlags member specifies KEYEVENTF_UNICODE, wVk must be 0.

wScan

Type: WORD

A hardware scan code for the key. If dwFlags specifies KEYEVENTF_UNICODE, wScan specifies a Unicode character which is to be sent to the foreground application.

dwFlags

Type: DWORD

Specifies various aspects of a keystroke. This member can be certain combinations of the following values.

Value Meaning
KEYEVENTF_EXTENDEDKEY
0x0001
 If specified, the wScan scan code consists of a sequence of two bytes, where the first byte has a value of 0xE0. See Extended-Key Flag for more info.
KEYEVENTF_KEYUP
0x0002
 If specified, the key is being released. If not specified, the key is being pressed.
KEYEVENTF_SCANCODE
0x0008
 If specified, wScan identifies the key and wVk is ignored.
KEYEVENTF_UNICODE
0x0004
 If specified, the system synthesizes a VK_PACKET keystroke. The wVk parameter must be zero. This flag can only be combined with the KEYEVENTF_KEYUP flag. For more information, see the Remarks section.

time

Type: DWORD

The time stamp for the event, in milliseconds. If this parameter is zero, the system will provide its own time stamp.

dwExtraInfo

Type: ULONG_PTR

An additional value associated with the keystroke. Use the GetMessageExtraInfo function to obtain this information.

Remarks

INPUT_KEYBOARD supports nonkeyboard-input methods—such as handwriting recognition or voice recognition—as if it were text input by using the KEYEVENTF_UNICODE flag. If KEYEVENTF_UNICODE is specified, SendInput sends a WM_KEYDOWN or WM_KEYUP message to the foreground thread's message queue with wParam equal to VK_PACKET. Once GetMessage or PeekMessage obtains this message, passing the message to TranslateMessage posts a WM_CHAR message with the Unicode character originally specified by wScan. This Unicode character will automatically be converted to the appropriate ANSI value if it is posted to an ANSI window.

Set the KEYEVENTF_SCANCODE flag to define keyboard input in terms of the scan code. This is useful for simulating a physical keystroke regardless of which keyboard is currently being used. You can also pass the KEYEVENTF_EXTENDEDKEY flag if the scan code is an extended key. The virtual key value of a key can change depending on the current keyboard layout or what other keys were pressed, but the scan code will always be the same.

Requirements

Requirement Value
Minimum supported client Windows 2000 Professional [desktop apps only]
Minimum supported server Windows 2000 Server [desktop apps only]
Header winuser.h (include Windows.h)

See also