WM_INPUTLANGCHANGEREQUEST message

Posted to the window with the focus when the user chooses a new input language, either with the hotkey (specified in the Keyboard control panel application) or from the indicator on the system taskbar. An application can accept the change by passing the message to the DefWindowProc function or reject the change (and prevent it from taking place) by returning immediately.

A window receives this message through its WindowProc function.

#define WM_INPUTLANGCHANGEREQUEST       0x0050

Parameters

wParam

The new input locale. This parameter can be a combination of the following flags.

Value Meaning
INPUTLANGCHANGE_BACKWARD
0x0004
A hot key was used to choose the previous input locale in the installed list of input locales. This flag cannot be used with the INPUTLANGCHANGE_FORWARD flag.
INPUTLANGCHANGE_FORWARD
0x0002
A hot key was used to choose the next input locale in the installed list of input locales. This flag cannot be used with the INPUTLANGCHANGE_BACKWARD flag.
INPUTLANGCHANGE_SYSCHARSET
0x0001
The new input locale's keyboard layout can be used with the system character set.

 

lParam

The input locale identifier. For more information, see Languages, Locales, and Keyboard Layouts.

Return value

Type: LRESULT

This message is posted, not sent, to the application, so the return value is ignored. To accept the change, the application should pass the message to DefWindowProc. To reject the change, the application should return zero without calling DefWindowProc.

Remarks

When the DefWindowProc function receives the WM_INPUTLANGCHANGEREQUEST message, it activates the new input locale and notifies the application of the change by sending the WM_INPUTLANGCHANGE message.

The language indicator is present on the taskbar only if you have installed more than one keyboard layout and if you have enabled the indicator using the Keyboard control panel application.

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

Reference

DefWindowProc

WM_INPUTLANGCHANGE

Conceptual

Windows