List of computers on the network

[gfrench]

I' sorry but there are not short cuts with this one, the code below is what you have to use, there is no shortening it.

It basically enumerates all network resources that are connectable and then from there it filters out everything except for machines, then they are placed in a listbox on frmMain

--Place this code in a module---

Public Const RESOURCE_CONNECTED As Long = &H1&
Public Const RESOURCE_GLOBALNET As Long = &H2&
Public Const RESOURCE_REMEMBERED As Long = &H3&

Public Const RESOURCEDISPLAYTYPE_SERVER& = &H2

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

Public Const RESOURCEUSAGE_ALL As Long = &H0&
Public Const RESOURCEUSAGE_CONNECTABLE As Long = &H1&
Public Const RESOURCEUSAGE_CONTAINER As Long = &H2&
Public Const RESOURCEUSAGE_RESERVED As Long = &H80000000

Public Const NO_ERROR = 0
Public Const ERROR_MORE_DATA = 234
Public Const RESOURCE_ENUM_ALL As Long = &HFFFF

Public Type NETRESOURCE
dwScope As Long
dwType As Long
dwDisplayType As Long
dwUsage As Long
pLocalName As Long
pRemoteName As Long
pComment As Long
pProvider As Long
End Type

Public Type NETRESOURCE_REAL
dwScope As Long
dwType As Long
dwDisplayType As Long
dwUsage As Long
sLocalName As String
sRemoteName As String
sComment As String
sProvider As String
End Type

Public Declare Function WNetAddConnection2 Lib "mpr.dll" Alias "WNetAddConnection2A" (lpNetResource As NETRESOURCE, ByVal lpPassword As String, ByVal lpUserName As String, ByVal dwFlags As Long) As Long
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, lpBuffer As NETRESOURCE, lpBufferSize As Long) As Long
Public Declare Function WNetCloseEnum Lib "mpr.dll" (ByVal hEnum As Long) As Long
Public Declare Function VarPtrAny Lib "vb40032.dll" Alias "VarPtr" (lpObject As Any) As Long
Public Declare Sub CopyMem Lib "kernel32" Alias "RtlMoveMemory" (lpTo As Any, lpFrom As Any, ByVal lLen As Long)
Public Declare Sub CopyMemByPtr Lib "kernel32" Alias "RtlMoveMemory" (ByVal lpTo As Long, ByVal lpFrom As Long, ByVal lLen As Long)
Public Declare Function lstrcpy Lib "kernel32" Alias "lstrcpyA" (ByVal lpString1 As String, ByVal lpString2 As Any) As Long
Public Declare Function lstrlen Lib "kernel32" Alias "lstrlenA" (ByVal lpString As Any) As Long










--Place this code where ever you want it--
Const MAX_RESOURCES = 256
Const NOT_A_CONTAINER = -1

Dim bFirstTime As Boolean
Dim lReturn As Long
Dim hEnum As Long
Dim lCount As Long
Dim lMin As Long
Dim lLength As Long
Dim l As Long
Dim lBufferSize As Long
Dim lLastIndex As Long
Dim uNetApi(0 To MAX_RESOURCES) As NETRESOURCE
Dim uNet() As NETRESOURCE_REAL

bFirstTime = True

Do
If bFirstTime Then
lReturn = WNetOpenEnum(RESOURCE_GLOBALNET, RESOURCETYPE_ANY, RESOURCEUSAGE_ALL, ByVal 0&, hEnum)
bFirstTime = False
Else
If uNet(lLastIndex).dwUsage And RESOURCEUSAGE_CONTAINER Then
lReturn = WNetOpenEnum(RESOURCE_GLOBALNET, RESOURCETYPE_ANY, RESOURCEUSAGE_ALL, uNet(lLastIndex), hEnum)
Else
lReturn = NOT_A_CONTAINER
hEnum = 0
End If
lLastIndex = lLastIndex + 1
End If
If lReturn = NO_ERROR Then
lCount = RESOURCE_ENUM_ALL
Do
lBufferSize = UBound(uNetApi) * Len(uNetApi(0)) / 2
lReturn = WNetEnumResource(hEnum, lCount, uNetApi(0), lBufferSize)
If lCount > 0 Then
ReDim Preserve uNet(0 To lMin + lCount - 1) As NETRESOURCE_REAL
For l = 0 To lCount - 1
'Each Resource will appear here as uNet(i)
uNet(lMin + l).dwScope = uNetApi(l).dwScope
uNet(lMin + l).dwType = uNetApi(l).dwType
uNet(lMin + l).dwDisplayType = uNetApi(l).dwDisplayType
uNet(lMin + l).dwUsage = uNetApi(l).dwUsage
If uNetApi(l).pLocalName Then
lLength = lstrlen(uNetApi(l).pLocalName)
uNet(lMin + l).sLocalName = Space$(lLength)
CopyMem ByVal uNet(lMin + l).sLocalName, ByVal uNetApi(l).pLocalName, lLength
End If
If uNetApi(l).pRemoteName Then
lLength = lstrlen(uNetApi(l).pRemoteName)
uNet(lMin + l).sRemoteName = Space$(lLength)
CopyMem ByVal uNet(lMin + l).sRemoteName, ByVal uNetApi(l).pRemoteName, lLength
End If
If uNetApi(l).pComment Then
lLength = lstrlen(uNetApi(l).pComment)
uNet(lMin + l).sComment = Space$(lLength)
CopyMem ByVal uNet(lMin + l).sComment, ByVal uNetApi(l).pComment, lLength
End If
If uNetApi(l).pProvider Then
lLength = lstrlen(uNetApi(l).pProvider)
uNet(lMin + l).sProvider = Space$(lLength)
CopyMem ByVal uNet(lMin + l).sProvider, ByVal uNetApi(l).pProvider, lLength
End If
Next l
End If
lMin = lMin + lCount
Loop While lReturn = ERROR_MORE_DATA
End If
If hEnum Then
l = WNetCloseEnum(hEnum)
End If
Loop While lLastIndex < lMin

If UBound(uNet) > 0 Then
For l = 0 To UBound(uNet)
Select Case uNet(l).dwDisplayType
Case Not RESOURCEDISPLAYTYPE_SERVER: Goto skip
Case RESOURCEDISPLAYTYPE_SERVER

End Select

'This is the bit that rights it to a list box
frmMain.List1.Clear
frmMain.List1.AddItem uNet(l).sRemoteName
skip:
Next l
End If


I hope this helps you out,

[Steven McGarva]

I have the same problem. gfrench posted Nice Code, but it does not work. Comments would have been good. Thanks for trying anyway. Guess I'll keep hacking away until I get it.

[gfrench]

The code does work, i have used it in one of my distributed applications (Remote Shutdown), if you want a demo project mail me and i will send it to you.

[gfrench]

Instructions
------------

Start A new project, with one form and one module
On the form place a Tree View control called treeview1

In FORM_LOAD place the code below:

refreshlist



In the module place the code below:

Private Const RESOURCE_CONNECTED As Long = &H1&
Private Const RESOURCE_GLOBALNET As Long = &H2&
Private Const RESOURCE_REMEMBERED As Long = &H3&

Private Const RESOURCEDISPLAYTYPE_DIRECTORY& = &H9
Private Const RESOURCEDISPLAYTYPE_DOMAIN& = &H1
Private Const RESOURCEDISPLAYTYPE_FILE& = &H4
Private Const RESOURCEDISPLAYTYPE_GENERIC& = &H0
Private Const RESOURCEDISPLAYTYPE_GROUP& = &H5
Private Const RESOURCEDISPLAYTYPE_NETWORK& = &H6
Private Const RESOURCEDISPLAYTYPE_ROOT& = &H7
Private Const RESOURCEDISPLAYTYPE_SERVER& = &H2
Private Const RESOURCEDISPLAYTYPE_SHARE& = &H3
Private Const RESOURCEDISPLAYTYPE_SHAREADMIN& = &H8

Private Const RESOURCETYPE_ANY As Long = &H0&
Private Const RESOURCETYPE_DISK As Long = &H1&
Private Const RESOURCETYPE_PRINT As Long = &H2&
Private Const RESOURCETYPE_UNKNOWN As Long = &HFFFF&

Public Const RESOURCEUSAGE_ALL As Long = &H0&
Public Const RESOURCEUSAGE_CONNECTABLE As Long = &H1&
Public Const RESOURCEUSAGE_CONTAINER As Long = &H2&
Public Const RESOURCEUSAGE_RESERVED As Long = &H80000000

Public Const NO_ERROR = 0
Public Const ERROR_MORE_DATA = 234
Public Const RESOURCE_ENUM_ALL As Long = &HFFFF

Public Type NETRESOURCE
dwScope As Long
dwType As Long
dwDisplayType As Long
dwUsage As Long
pLocalName As Long
pRemoteName As Long
pComment As Long
pProvider As Long
End Type

Public Type NETRESOURCE_REAL
dwScope As Long
dwType As Long
dwDisplayType As Long
dwUsage As Long
sLocalName As String
sRemoteName As String
sComment As String
sProvider As String
End Type

Public Declare Function WNetAddConnection2 Lib "mpr.dll" Alias "WNetAddConnection2A" (lpNetResource As NETRESOURCE, ByVal lpPassword As String, ByVal lpUserName As String, ByVal dwFlags As Long) As Long
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, lpBuffer As NETRESOURCE, lpBufferSize As Long) As Long
Public Declare Function WNetCloseEnum Lib "mpr.dll" (ByVal hEnum As Long) As Long

Public Declare Function VarPtrAny Lib "vb40032.dll" Alias "VarPtr" (lpObject As Any) As Long

Public Declare Sub CopyMem Lib "kernel32" Alias "RtlMoveMemory" (lpTo As Any, lpFrom As Any, ByVal lLen As Long)
Public Declare Sub CopyMemByPtr Lib "kernel32" Alias "RtlMoveMemory" (ByVal lpTo As Long, ByVal lpFrom As Long, ByVal lLen As Long)

Public Declare Function lstrcpy Lib "kernel32" Alias "lstrcpyA" (ByVal lpString1 As String, ByVal lpString2 As Any) As Long
Public Declare Function lstrlen Lib "kernel32" Alias "lstrlenA" (ByVal lpString As Any) As Long



Public Sub RefreshList()


Const MAX_RESOURCES = 256
Const NOT_A_CONTAINER = -1


Dim bFirstTime As Boolean
Dim lReturn As Long
Dim hEnum As Long
Dim lCount As Long
Dim lMin As Long
Dim lLength As Long
Dim l As Long
Dim lBufferSize As Long
Dim lLastIndex As Long
Dim uNetApi(0 To MAX_RESOURCES) As NETRESOURCE
Dim uNet() As NETRESOURCE_REAL


frmMain.TreeView1.Nodes.Clear 'Clear the treeview1 control on frmMain

bFirstTime = True 'Make code below aware that that it is the first loop




Do
DoEvents
If bFirstTime Then 'If this is the first time the loop has executed then

'Start the enumeration of all network resources
lReturn = WNetOpenEnum(RESOURCE_GLOBALNET, RESOURCETYPE_DISK, RESOURCEUSAGE_ALL, ByVal 0&, hEnum) 'Get a handle to a buffer

'The next time it reaches the if bfirsttime then line it will not be the first time
bFirstTime = False

Else

If uNet(lLastIndex).dwUsage And RESOURCEUSAGE_CONTAINER Then

lReturn = WNetOpenEnum(RESOURCE_GLOBALNET, RESOURCETYPE_DISK, RESOURCEUSAGE_ALL, uNet(lLastIndex), hEnum) 'Initiate the enumeration process

Else

lReturn = NOT_A_CONTAINER 'Set the returnvalue to NOT_A_CONTAINER for later reference
hEnum = 0

End If

lLastIndex = lLastIndex + 1 'Increase the network resource number by 1 (array number)

End If


If lReturn = NO_ERROR Then 'If there was no error then procress the data retrieved

lCount = RESOURCE_ENUM_ALL 'Enumerate all resoureces

Do
DoEvents

lBufferSize = UBound(uNetApi) * Len(uNetApi(0)) / 2 'Set the buffer size
lReturn = WNetEnumResource(hEnum, lCount, uNetApi(0), lBufferSize) 'Get resource information

If lCount > 0 Then

'The next bit copys the information from memory to uNetApi array
ReDim Preserve uNet(0 To lMin + lCount - 1) As NETRESOURCE_REAL

For l = 0 To lCount - 1

uNet(lMin + l).dwScope = uNetApi(l).dwScope
uNet(lMin + l).dwType = uNetApi(l).dwType
uNet(lMin + l).dwDisplayType = uNetApi(l).dwDisplayType
uNet(lMin + l).dwUsage = uNetApi(l).dwUsage


If uNetApi(l).pLocalName Then

lLength = lstrlen(uNetApi(l).pLocalName)
uNet(lMin + l).sLocalName = Space$(lLength)
CopyMem ByVal uNet(lMin + l).sLocalName, ByVal uNetApi(l).pLocalName, lLength

End If


If uNetApi(l).pRemoteName Then

lLength = lstrlen(uNetApi(l).pRemoteName)
uNet(lMin + l).sRemoteName = Space$(lLength)
CopyMem ByVal uNet(lMin + l).sRemoteName, ByVal uNetApi(l).pRemoteName, lLength

End If


If uNetApi(l).pComment Then

lLength = lstrlen(uNetApi(l).pComment)
uNet(lMin + l).sComment = Space$(lLength)
CopyMem ByVal uNet(lMin + l).sComment, ByVal uNetApi(l).pComment, lLength

End If


If uNetApi(l).pProvider Then

lLength = lstrlen(uNetApi(l).pProvider)
uNet(lMin + l).sProvider = Space$(lLength)
CopyMem ByVal uNet(lMin + l).sProvider, ByVal uNetApi(l).pProvider, lLength

End If

Next l

End If

lMin = lMin + lCount

Loop While lReturn = ERROR_MORE_DATA

End If

If hEnum Then l = WNetCloseEnum(hEnum)

Loop While lLastIndex < lMin


If UBound(uNet) > 0 Then

For l = 0 To UBound(uNet)

DoEvents

'Select what type of resource it is (there are more but these are the only ones that we want
Select Case uNet(l).dwDisplayType


Case RESOURCEDISPLAYTYPE_DOMAIN
frmMain.TreeView1.Nodes.Add , 2, uNet(l).sRemoteName, uNet(l).sRemoteName, "Domain", "Domain"
CurrentDomain = uNet(l).sRemoteName


Case RESOURCEDISPLAYTYPE_SERVER
If CurrentDomain <> "" Then
frmMain.TreeView1.Nodes.Add CurrentDomain, 4, uNet(l).sRemoteName, Mid$(uNet(l).sRemoteName, 3, Len(uNet(l).sRemoteName) - 2), "Computer", "Computer"
Else
frmMain.TreeView1.Nodes.Add , 2, uNet(l).sRemoteName, Mid$(uNet(l).sRemoteName, 3, Len(uNet(l).sRemoteName) - 2), "Computer", "Computer"
End If


End Select

Next l

End If

End Sub




This code works, and curses to any one who says it doesnt with cause.

This will Help you,

[kurtsimons]

Tested on on windows NT...


if you want it simplier (but not as clean)

batch the command

net view


that will show you the computers then

net view [computername]

will show you its resources

[rob de jong]

Works fine for me (W2000) ! (and is exactly what i'm looking for). One extra: is it possible to show hidden shares (like c$)?

[kurtsimons]

No, I don't think so.