VC++ MapVirtualKeyEx

MapVirtualKeyEx Function

The MapVirtualKeyEx function translates (maps) a virtual-key code into a scan code or character value, or translates a scan code into a virtual-key code. The function translates the codes using the input language and an input locale identifier.

Syntax

UINT MapVirtualKeyEx(      
    UINT uCode,    UINT uMapType,    HKL dwhkl);

Parameters

uCode

[in] Specifies the virtual-key code or scan code for a key. How this value is interpreted depends on the value of the uMapType parameter.

uMapType

[in] Specifies the translation to perform. The value of this parameter depends on the value of the uCode parameter.

MAPVK_VK_TO_VSC

The uCode parameter is a virtual-key code and is translated into a scan code. If it is a virtual-key code that does not distinguish between left- and right-hand keys, the left-hand scan code is returned. If there is no translation, the function returns 0.

MAPVK_VSC_TO_VK

The uCode parameter is a scan code and is translated into a virtual-key code that does not distinguish between left- and right-hand keys. If there is no translation, the function returns 0.

Windows Vista and later: The high byte of the uCode value can contain either 0xe0 or 0xe1 to specify the extended scan code.

MAPVK_VK_TO_CHAR

The uCode parameter is a virtual-key code and is translated into an unshifted character value in the low order word of the return value. Dead keys (diacritics) are indicated by setting the top bit of the return value. If there is no translation, the function returns 0.

MAPVK_VSC_TO_VK_EX

Windows NT/2000/XP and later: uCode is a scan code and is translated into a virtual-key code that distinguishes between left- and right-hand keys. If there is no translation, the function returns 0.

Windows Vista and later: The high byte of the uCode value can contain either 0xe0 or 0xe1 to specify the extended scan code.

MAPVK_VK_TO_VSC_EX

Windows Vista and later: The uCode parameter is a virtual-key code and is translated into a scan code. If it is a virtual-key code that does not distinguish between left- and right-hand keys, the left-hand scan code is returned. If the scan code is an extended scan code, the high byte of the uCode value can contain either 0xe0 or 0xe1 to specify the extended scan code. If there is no translation, the function returns 0.

dwhkl

[in] Input locale identifier to use for translating the specified code. This parameter can be any input locale identifier previously returned by the LoadKeyboardLayout function.

Return Value

The return value is either a scan code, a virtual-key code, or a character value, depending on the value of uCode and uMapType. If there is no translation, the return value is zero.

Remarks

The input locale identifier is a broader concept than a keyboard layout, since it can also encompass a speech-to-text converter, an Input Method Editor (IME), or any other form of input.

An application can use MapVirtualKeyEx to translate scan codes to the virtual-key code constants VK_SHIFT, VK_CONTROL, and VK_MENU, and vice versa. These translations do not distinguish between the left and right instances of the SHIFT, CTRL, or ALT keys.

Windows NT/2000/XP: An application can get the scan code corresponding to the left or right instance of one of these keys by calling MapVirtualKeyEx with uCode set to one of the following virtual-key code constants.

• VK_LSHIFT
• VK_RSHIFT
• VK_LCONTROL
• VK_RCONTROL
• VK_LMENU
• VK_RMENU

These left- and right-distinguishing constants are available to an application only through the GetKeyboardState, SetKeyboardState, GetAsyncKeyState, GetKeyState, MapVirtualKey, and MapVirtualKeyEx functions. For list complete table of virtual key codes, see Virtual Key Codes.

Windows 95/98/Me: MapVirtualKeyExW is supported by the Microsoft Layer for Unicode (MSLU). To use this, you must add certain files to your application, as outlined in Microsoft Layer for Unicode on Windows 95/98/Me Systems.