messagehandler.md

description	title	ms.date	ms.topic	helpviewer_keywords	ms.assetid
Learn more about: MessageHandler	MessageHandler	11/04/2016	reference	MessageHandler function	8a0acf97-1b0d-4226-91b9-75446634a03c

MessageHandler

MessageHandler is the name of the function identified by the second parameter of the MESSAGE_HANDLER macro in your message map.

Syntax

LRESULT MessageHandler(
    UINT uMsg,
    WPARAM wParam,
    LPARAM lParam,
    BOOL& bHandled);

Parameters

uMsg
Specifies the message.

wParam
Additional message-specific information.

lParam
Additional message-specific information.

bHandled
The message map sets bHandled to TRUE before MessageHandler is called. If MessageHandler does not fully handle the message, it should set bHandled to FALSE to indicate the message needs further processing.

Return Value

The result of message processing. 0 if successful.

Remarks

For an example of using this message handler in a message map, see MESSAGE_HANDLER.

See also

Implementing a Window
Message Maps
WM_NOTIFY