Network Computers

[Gary007]

Is there a way to enumerate all of the computers currently connected to a Windows 95/98 LAN.

[Edited by Gary007 on 08-05-2000 at 06:06 AM]

[cas21]

'Paste this into a module

Option Explicit

Public Type NETRESOURCE
dwScope As Long
dwType As Long
dwDisplayType As Long
dwUsage As Long
lpLocalName As Long
lpRemoteName As Long
lpComment As Long
lpProvider As Long
End Type

Public Declare Function WNetOpenEnum Lib "mpr.dll" Alias _
"WNetOpenEnumA" ( _
ByVal dwScope As Long, _
ByVal dwType As Long, _
ByVal dwUsage As Long, _
lpNetResource As Any, _
lphEnum As Long) As Long

Public Declare Function WNetEnumResource Lib "mpr.dll" Alias _
"WNetEnumResourceA" ( _
ByVal hEnum As Long, _
lpcCount As Long, _
ByVal lpBuffer As Long, _
lpBufferSize As Long) As Long

Public Declare Function WNetCloseEnum Lib "mpr.dll" ( _
ByVal hEnum As Long) As Long

'RESOURCE ENUMERATION.
Public Const RESOURCE_CONNECTED = &H1
Public Const RESOURCE_GLOBALNET = &H2
Public Const RESOURCE_REMEMBERED = &H3

Public Const RESOURCETYPE_ANY = &H0
Public Const RESOURCETYPE_DISK = &H1
Public Const RESOURCETYPE_PRINT = &H2
Public Const RESOURCETYPE_UNKNOWN = &HFFFF

Public Const RESOURCEUSAGE_CONNECTABLE = &H1
Public Const RESOURCEUSAGE_CONTAINER = &H2
Public Const RESOURCEUSAGE_RESERVED = &H80000000

Private Const GMEM_FIXED = &H0
Private Const GMEM_ZEROINIT = &H40
Private Const GPTR = (GMEM_FIXED Or GMEM_ZEROINIT)

Private Declare Function GlobalAlloc Lib "KERNEL32" (ByVal wFlags As Long, ByVal dwBytes As Long) As Long
Private Declare Function GlobalFree Lib "KERNEL32" (ByVal hMem As Long) As Long
Private Declare Sub CopyMemory Lib "KERNEL32" Alias "RtlMoveMemory" (hpvDest As Any, hpvSource As Any, ByVal cbCopy As Long)
Private Declare Function CopyPointer2String Lib "KERNEL32" Alias "lstrcpyA" (ByVal NewString As String, ByVal OldString As Long) As Long

Public Sub DoNetEnum()
Dim hEnum As Long, lpBuff As Long, NR As NETRESOURCE
Dim cbBuff As Long, cCount As Long
Dim p As Long, res As Long, i As Long

'Setup the NETRESOURCE input structure.
NR.lpRemoteName = 0
cbBuff = 10000
cCount = &HFFFFFFFF


'Open a Net enumeration operation handle: hEnum.
res = WNetOpenEnum(RESOURCE_GLOBALNET, RESOURCETYPE_ANY, 0, NR, hEnum)

If res = 0 Then
'Create a buffer large enough for the results.
'10000 bytes should be sufficient.
lpBuff = GlobalAlloc(GPTR, cbBuff)
'Call the enumeration function.
res = WNetEnumResource(hEnum, cCount, lpBuff, cbBuff)
If res = 0 Then
p = lpBuff
'WNetEnumResource fills the buffer with an array of
'NETRESOURCE structures. Walk through the list and print
'each local and remote name.
For i = 1 To cCount
' All we get back are the Global Network Containers --- Enumerate each of these
CopyMemory NR, ByVal p, LenB(NR)
Form1.Show
Form1.List1.AddItem "Network Name " & PointerToString(NR.lpRemoteName)

DoNetEnum2 NR
p = p + LenB(NR)
Next i
End If
If lpBuff <> 0 Then GlobalFree (lpBuff)
WNetCloseEnum (hEnum) 'Close the enumeration
End If
End Sub

Private Function PointerToString(p As Long) As String
'The values returned in the NETRESOURCE structures are pointers to
'ANSI strings so they need to be converted to Visual Basic Strings.
Dim s As String
s = String(255, Chr$(0))
CopyPointer2String s, p
PointerToString = Left(s, InStr(s, Chr$(0)) - 1)
End Function

Public Sub DoNetEnum2(NR As NETRESOURCE)
Dim hEnum As Long, lpBuff As Long
Dim cbBuff As Long, cCount As Long
Dim p As Long, res As Long, i As Long

'Setup the NETRESOURCE input structure.
cbBuff = 10000
cCount = &HFFFFFFFF

'Open a Net enumeration operation handle: hEnum.

res = WNetOpenEnum(RESOURCE_GLOBALNET, RESOURCETYPE_ANY, 0, NR, hEnum)

If res = 0 Then
'Create a buffer large enough for the results.
'10000 bytes should be sufficient.
lpBuff = GlobalAlloc(GPTR, cbBuff)
'Call the enumeration function.
res = WNetEnumResource(hEnum, cCount, lpBuff, cbBuff)
If res = 0 Then
p = lpBuff
'WNetEnumResource fills the buffer with an array of
'NETRESOURCE structures. Walk through the list and print
'each remote name.
For i = 1 To cCount
CopyMemory NR, ByVal p, LenB(NR)
Form1.List1.AddItem "Network Computer #" & i & " " & PointerToString(NR.lpRemoteName)
p = p + LenB(NR)
Next i
End If
If lpBuff <> 0 Then GlobalFree (lpBuff)
WNetCloseEnum (hEnum) 'Close the enumeration
Else
End If
End Sub


'This is for form1 which has a list1

Private Sub Form_Load()
DoNetEnum

End Sub