Does anyone know how I can detect a network connection.

[bluelocust]

I need to detect whether or not I currently have a network connection. I am on a LAN not a dialup.

Any solutions...

[dmr]

When you are not directly connected to the internet you can't detect if you are. You could try to ping a site and when you get an answer you're connected but I don't see direct way.

Or you install a server-application on the server which sends you the current connectionstate via LAN to a client-app...


Or do you just want to know if you have an active LAN-Connection?

[Stryker]

For info on how to determine if your internet connection is via a LAN, take a look in the Previous Topic.

To detect if you are on a LAN with no internet connection, well ... I'll get back

[bluelocust]

Thanx for the input Stryker. Worked great.

If you come up with how to detect a LAN without an internet connection I'd be very interested

[daugman]

Just try and find another computer on the LAN (or a known server).

That's what we do for our VB/ASP app... I try and map to the server, and if it's not available -- it'll tell me...

I'll see if I can find the code and post tomorrow. It's part of the WNetOpenEnum API - one of the errors will return is ERROR_NO_NETWORK.

I don't have the VB code handy but :

DWORD WNetOpenEnum(
  DWORD dwScope,     // scope of enumeration
  DWORD dwType,      // resource types to list
  DWORD dwUsage,     // resource usage to list
  LPNETRESOURCE lpNetResource,
                     // pointer to resource structure
  LPHANDLE lphEnum   // pointer to enumeration handle buffer
);

[daugman]

Ah ha! I found it :P

Public Sub ListDomainComputers(p_strDomain As String, p_colUse As Collection)
    
    Dim tNetRes As NETRES2
    Dim lngRet As Long
    Dim lngHndEnum As Long
    
    On Error Resume Next
    
    With tNetRes
        .lpRemoteName = p_strDomain
        .dwDisplayType = 1
    End With
    
    lngRet = WNetOpenEnum(RESOURCE_GLOBALNET, RESOURCETYPE_DISK, 0, tNetRes, lngHndEnum)
    
    If lngRet <> 0 Then ' check for ERROR_NO_NETWORK here!!! 
        MsgBox "Error getting computers on the LAN.", vbCritical, "Error"
        Exit Sub
    End If
.
.
.

This will tell you if the network if available or not.