Send messages between processes (send and receive system messages)

{
2002.07.22
About how to send and receive system messages
Author: Wang Zhenyi
Nickname: largewang (Lao Wang)
QQ: 33728007
Welcome to pengye software www.pengesoft.com.cn

Run the following code Delphi7.0. After compiling, start two processes and click button1 in a window.
}

Unit unit1;

Interface

Uses
Windows, messages, sysutils, variants, classes, graphics, controls, forms,
Dialogs, stdctrls;

Type
Tform1 = Class (tform)
Button1: tbutton;
Procedure formcreate (Sender: tobject );
Procedure button1click (Sender: tobject );
Private
MSG: longint;
{Private Declarations}
Protected
Procedure wndproc (VAR message: tmessage); override;
Public

{Public declarations}
End;

VaR
Form1: tform1;

Implementation

{$ R *. DFM}

Procedure tform1.formcreate (Sender: tobject );
Begin
MSG: = registerwindowmessage ('wm _ mymessage ');
Self. bringtofront;
End;

Procedure tform1.wndproc (VAR message: tmessage );
Begin
If message. MSG = MSG then begin
Caption: = '';
Showmessage ('Received message ');
End
Else begin
Inherited;
End;
End;

Procedure tform1.button1click (Sender: tobject );
VaR
M: tmessage;
B: DWORD;
Begin
M. MSG: = MSG;
B: = bsm_allcomponents;
Broadcastsystemmessage (bsf_postmessage, @ B, M. MSG, M. wparam, M. lparam );
End;

End.

//// Window file
Object form1: tform1
Left = 1, 192
Maximum = 107
Width = 696
Height = 480
Caption = 'form1'
Color = clbtnface
Font. charset = default_charset
Font. Color = clwindowtext
Font. Height =-11
Font. Name = 'Ms sans serif'
Font. Style = []
Oldcreateorder = false
Oncreate = formcreate
Pixelsperinch = 96
Textheight = 13
Object button1: tbutton
Left = 1, 204
Top = 84
Width = 75
Height = 25
Caption = 'button1'
Taborder = 0
Onclick = button1click
End
End