Broadcast network message

How can I send a message from the administrator to all (or some) users in the network using Delphi?

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Here's an example - Hope it helps
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unit Unit1;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls;

type
TForm1 = class(TForm)
Button1: TButton;
procedure Button1Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;

var
Form1: TForm1;

implementation

{$R *.dfm}
function NetSend(dest, Source, Msg: string): Longint; overload;
type
TNetMessageBufferSendFunction = function(servername, msgname, fromname: PWideChar;
buf: PWideChar; buflen: Cardinal): Longint;
stdcall;
var
NetMessageBufferSend: TNetMessageBufferSendFunction;
SourceWideChar: PWideChar;
DestWideChar: PWideChar;
MessagetextWideChar: PWideChar;
Handle: THandle;
begin
Handle := LoadLibrary('NETAPI32.DLL');
if Handle = 0 then
begin
Result := GetLastError;
Exit;
end;
@NetMessageBufferSend := GetProcAddress(Handle, 'NetMessageBufferSend');
if @NetMessageBufferSend = nil then
begin
Result := GetLastError;
Exit;
end;

MessagetextWideChar := nil;
SourceWideChar := nil;
DestWideChar := nil;

try
GetMem(MessagetextWideChar, Length(Msg) * SizeOf(WideChar) + 1);
GetMem(DestWideChar, 20 * SizeOf(WideChar) + 1);
StringToWideChar(Msg, MessagetextWideChar, Length(Msg) * SizeOf(WideChar) + 1);
StringToWideChar(Dest, DestWideChar, 20 * SizeOf(WideChar) + 1);

if Source = '' then
Result := NetMessageBufferSend(nil, DestWideChar, nil,
MessagetextWideChar, Length(Msg) * SizeOf(WideChar) + 1)
else
begin
GetMem(SourceWideChar, 20 * SizeOf(WideChar) + 1);
StringToWideChar(Source, SourceWideChar, 20 * SizeOf(WideChar) + 1);
Result := NetMessageBufferSend(nil, DestWideChar, SourceWideChar,
MessagetextWideChar, Length(Msg) * SizeOf(WideChar) + 1);
FreeMem(SourceWideChar);
end;
finally
FreeMem(MessagetextWideChar);
FreeLibrary(Handle);
end;
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
NetSend('Silver','Silver','Yoooooooo');
end;

end.

Hi,

I tried you code by just changing the dest and source but I am not getting any messages sent..

Here is my code:

NetSend('rahma-j','rahma-j','Yoooooooo');


Best Regards,
Jassim Rahma

This only works on windows nt platforms and it's a replacement of the command line "net send IP/computer_name message", it does not work on Win 95, 98, ME.
If you are interested in a chat there are a couple of freeware products out there that can do the job.

thanks,


i don't want chat application.


I am using Windows XP

There is a service in Win Xp named "Messenger" that deals with the "net send" ... make sure it is started.

hello

hello