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4/8/2010

This function is an application-defined callback function that processes messages sent to a window.

Syntax 

LRESULT CALLBACK WindowProc(
  HWND 
hwnd, 
  UINT 
uMsg, 
  WPARAM 
wParam, 
  LPARAM 
lParam 
);

Parameters

hwnd

[in] Handle to the window.

uMsg

[in] Specifies the message.

wParam

[in] Specifies additional message information. The contents of this parameter depend on the value of the uMsgparameter.

lParam

[in] Specifies additional message information. The contents of this parameter depend on the value of the uMsgparameter.

Return Value

The return value is the result of the message processing and depends on the message sent.

Requirements

Header winuser.h
Windows Embedded CE Windows CE 1.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also