Message through LAN vb 2005

[sunilmaloo2003]

Hi vbeans, happy MakaraSankranti....

I want to create a program which should run only at my system and when i enter a message in a textbox and click SEND button then the message will display all the other computers in the LAN. I can not install any program in any other computers. I know all the IPs of other coumputers. Is it possible in vb 2005? I tried to make a program with NET SEND but failed because some computers are XP based and some are VISTA based and some are win 2000 based. Message is not displaying. Please help....Thanks in advance... Sunil Nair

[Shaggy Hiker]

Would you really expect such a program to run? That would require that the OS allow an external program to cause something to be written to the screen. Your intention might be benign, but if you can write a small message to the screen of a remote system without anything being installed on the remote system, then why couldn't somebody else start firing either messages so large that they fill the screen, or messages so fast that the target system is brought to its knees just showing those messages. Basically, this would be a MAJOR security liability.

Of course, there ARE programs that do something like that, but they all require that somebody install something on the target computers.

[sunilmaloo2003]

Thank you for your kind reply. I am not intend to do any disturbances with other system of our LAN. My Boss want to give messages to some or all of the staff through his System via LAN. He asked me to develop a program to do such Announcing things. Our LAN consist of more than 80 PCs hence it is very difficult (Not Impossible) to install any program in all of the PCs. Can you give me any idea to do it? If it is important to install program in all other PCs, I can do it too. Please give me some suggestions...

[Hack]

It would be important to install something on all machines.

Basically, however, what you are talking about is building an internal Chat program, right?

[Shaggy Hiker]

Considering that this is coming from the boss, I would suggest that you write something and have everybody install it themselves, unless they don't have the technical skill. Since this is inside a LAN, security is much less of an issue. The program on the client system will just be listening to a port waiting for a message to come through, and when one does it pops up a messagebox with the message.

This is a one-way chat application, and the listeners can be correspondingly simple, since they may not have to send anything back. However, there really does need to be a listener. Of course, I happen to have such software installed on my computer, and whenever my boss (or anybody else) sends me a message, a little window pops up with something like "You've got mail".

[sunilmaloo2003]

Thanks. You r right that it will be a one sided chat program. I really do not know how to create a pop up message in vb 2005. But i did the same in vb6. Can you give me some clues about it?

[sunilmaloo2003]

I have googled a lot to find a code for chat in vb 2005. I referred 101 samples and also no code for such facility. Oneside chat and Pop up. Can u show me the code or a link to that?

[Hack]

Does this help?

[Doogle]

Deleted contents:
Suggested using Net Send but I now see that op has already tried that.

[sunilmaloo2003]

Sir, actually i need a one sided chat program and i dont want to install the software everywhere. I can install one software in every system but i cannot install winsock and such things in any other systems. I did it with vb6 but do not know how in vb 2005. Please send me some code...

[Atheist]

You did it in VB6? May I ask how?

[sunilmaloo2003]

By using winsock. I installed the same program in several systems. I made some registry changes so that it will automatically start at the start-up and hide at notification area. when ever i send a message to any other system, it will pop-up a message on the user's screen. It was simple. Winsock helped a lot. But now it is vb 2005. I used win sock at 2005 also. But it did not work well.

[sunilmaloo2003]

Atheist, if you want to see the program, i can send to you.

[Atheist]

Atheist, if you want to see the program, i can send to you.

No thats alright
The reason I was asking is, you made it sound as if you had managed, in vb6, to send messages to other computers without needing to install software on them.

So where are you going from here? You wont be able to send messages to the other computers without installing the application on their computers. If you still wish to continue, search the forum for any of the following: TCP, UDP, Sockets.
You may also want to search MSDN as they've got some good examples aswell.

[dilettante]

The reason I was asking is, you made it sound as if you had managed, in vb6, to send messages to other computers without needing to install software on them.

Of course you can.

This assumes the Messenger Service (nothing to do with Windows Messenger or MSN Messenger) is running though... which of course means you really do rely on software on the remote machines.

The NET SEND command just sends mailslot datagrams, which a VB6 program can do too.


Because of abuses and a superstitious confusion between the Messenger Service and so-called Messenger Spam (which has nothing to do with the Messenger Service), in many settings the Messenger Service is disabled.

Nothing prevents you from creating your own programs that work in a similar fashion. For an in-house LAN I'd use a mailslot instead of a TCP or UDP port. You don't risk port number collisions or have to deal with software firewalls on the PCs. Mailslots work over the standard "File and Print Sharing" facilities in a Windows network.