WindowProc Callback Function

Public Function WindowProc (ByVal hwnd As Long, ByVal uMsg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
  ' application-defined code goes here
End Function

Description & Usage

The WindowProc hook function acts as the window procedure of a window. The window procedure processes all of the messages received by that window. The function does not actually have to be named WindowProc; that is just the name given to it in discussions about the API.

Return Value

The return value depends on the requirements of the message being processed.

Visual Basic-Specific Issues

Like all callback functions, WindowProc must be declared Public and be defined in a module.

Parameters

hwnd

A handle to the window which has received the message.

uMsg

The message to be acted upon.

wParam

Additional information about the message.

lParam

Additional information about the message.

Used By

CallWindowProc, GetClassLong, GetWindowLong, SetClassLong, SetWindowLong, WNDCLASS, WNDCLASSEX

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Last Modified: August 22, 1999
This page is copyright © 1999 Paul Kuliniewicz. Copyright Information Revised October 29, 2000
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