How to check if Network PC is online

[bulletrick]

Guys, how do I check if a PC connected to a network is online?

I created a program that will distribute a file to all IP addresses given.

My problem is, when the user gives an IP that is offline (turned off or not connected to the network), the program hangs for a few seconds while executing the FileCopy procedure then returns an error that the path can't be found.

I wanted to prevent the hang up and I think I can do that by checking first if the IP is online before going to the FileCopy procedure.

Thanks a lot guys!

[HoraShadow]

Ping the IP?

[bulletrick]

Ping the IP?

Good idea.. How do I do that in VB?

[the182guy]

you could just connect to the IP on port 80. Port 80 will accept connections on most hosts.

so have a winsock on the form and use this

Winsock1.Connect strIP, 80

heres the Winsock Connect sub

Private Sub Winsock1_Connect()
     'Connected! so the host must be online
     Winsock1.Close 'Disconnect the socket & return to closed state
End Sub

The winsock error sub

Private Sub Winsock1_Error(ByVal Number As Integer, Description As String, ByVal Scode As Long, ByVal Source As String, ByVal HelpFile As String, ByVal HelpContext As Long, CancelDisplay As Boolean)
     'Socket errored so it didnt connect - the host is not online
     Winsock1.Close 'Return its state to closed
End Sub

[bulletrick]

the182guy: this works even if the PC don't have a VB program w/ winsock? as long as the PC is connected and online? thanks!

[the182guy]

the182guy: this works even if the PC don't have a VB program w/ winsock? as long as the PC is connected and online? thanks!

the computer that your trying to find out the online status of does not need any vb app on it.

[bulletrick]

the computer that your trying to find out the online status of does not need any vb app on it.

Ok. thanks a lot! That's what I needed. Try it later. Thanks again!

[the182guy]

Ok. thanks a lot! That's what I needed. Try it later. Thanks again!

alright no probs, post back if you have problems

[bulletrick]

Hello 182guy!

Uhhh.. the code did not work...

[the182guy]

did you set the IP? you should change the 'strIP' to the network target IP address

[bulletrick]

did you set the IP? you should change the 'strIP' to the network target IP address

Hehe. Of course.. I know that. I used "192.0.1.170", 80.

[the182guy]

you could get the list of connected terminals to the LAN, then you could check the list if the specified terminal is connected, I posted an example on how to do this here:
http://www.vbforums.com/showthread.php?t=391595