I need to refresh Window's list of wireless networks.
I'll gladly accept any workaround that I can automate (cmdline, wmi, etc) directly or indirectly from VBA. (I'm using Windows 7 Home 64-bit with Office 365 Pro 64-bit.)
I can list the networks programmatically a couple ways including netsh
, or the code below, but the list does not refresh unless I physically click the Network Connection icon on the taskbar's Notification area.
- The list does not auto-update every 60 seconds as some docs state.
- Disconnect+Reconnecting the NIC is not a feasible/sustainable option.
I think I'm not getting the handle from WlanOpenHandle as required and I'm green at converting C to VBA.
No errors but WlanScan returns unknown code 1168
.
- I adapted from the VB version here: wlanscan (wlanapi)
- MSDN documentation: WlanScan function
Related bits:
Here's the function declaration for VB
, adapted:
Public Shared Function WlanScan(ByVal hClientHandle As IntPtr, _
ByRef pInterfaceGuid As Guid, ByVal pDot11Ssid As IntPtr, _
ByVal pIeData As IntPtr, ByVal pReserved As IntPtr) As UInteger
End Function
...and an example of function usage in C#
:
Guid g;
//wlanHndl is the handle returned previously by calling [WlanOpenHandle]
for (int i = 0; i < infoList.dwNumberOfItems; i++)
{
g = infoList.InterfaceInfo[i].InterfaceGuid;
uint resultCode=WlanScan(wlanHndl, ref g, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero);
if (resultCode != 0)
return;
}
...and how to open the handle, in C++
(from here):
dwResult = WlanOpenHandle(dwMaxClient, NULL, &dwCurVersion, &hClient);
if (dwResult != ERROR_SUCCESS) {
wprintf(L"WlanOpenHandle failed with error: %u\n", dwResult);
return 1;
// You can use FormatMessage here to find out why the function failed
}
"Un-hidden:"
Obtain (cached) list of wireless networks:
The code to list the networks works great - except for not refreshing on it's own. (Previously I was parsing the text output of netsh wlan show networks mode=bssid
, which had the same issue.)
I had previously removed this section because its lengthy and seems to work fine except for the refresh. -)
Option Explicit 'section's source: vbforums.com/showthread.php?632731
Private Const DOT11_SSID_MAX_LENGTH As Long = 32
Private Const WLAN_MAX_PHY_TYPE_NUMBER As Long = 8
Private Const WLAN_AVAILABLE_NETWORK_CONNECTED As Long = 1
Private Const WLAN_AVAILABLE_NETWORK_HAS_PROFILE As Long = 2
Private Type GUID 'from cpearson.com
Data1 As Long: Data2 As Integer: Data3 As Integer: Data4(7) As Byte
End Type
Private Type WLAN_INTERFACE_INFO
ifGuid As GUID: InterfaceDescription(255) As Byte: IsState As Long
End Type
Private Type DOT11_SSID
uSSIDLength As Long: ucSSID(DOT11_SSID_MAX_LENGTH - 1) As Byte
End Type
Private Type WLAN_AVAILABLE_NETWORK
strProfileName(511) As Byte: dot11Ssid As DOT11_SSID
dot11BssType As Long: uNumberOfBssids As Long
bNetworkConnectable As Long: wlanNotConnectableReason As Long
uNumberOfPhyTypes As Long: dot11PhyTypes(WLAN_MAX_PHY_TYPE_NUMBER - 1) As Long
bMorePhyTypes As Long: wlanSignalQuality As Long
bSEcurityEnabled As Long: dot11DefaultAuthAlgorithm As Long
dot11DefaultCipherAlgorithm As Long: dwflags As Long: dwReserved As Long
End Type
Private Type WLAN_INTERFACE_INFO_LIST
dwNumberOfItems As Long: dwIndex As Long: InterfaceInfo As WLAN_INTERFACE_INFO
End Type
Private Type WLAN_AVAILABLE_NETWORK_LIST
dwNumberOfItems As Long: dwIndex As Long: Network As WLAN_AVAILABLE_NETWORK
End Type
Declare PtrSafe Function WlanOpenHandle Lib "Wlanapi.dll" (ByVal dwClientVersion As Long, _
ByVal pdwReserved As Long, ByRef pdwNegotiaitedVersion As Long, _
ByRef phClientHandle As Long) As Long
Declare PtrSafe Function WlanEnumInterfaces Lib "Wlanapi.dll" (ByVal hClientHandle As Long, _
ByVal pReserved As Long, ppInterfaceList As Long) As Long
Declare PtrSafe Function WlanGetAvailableNetworkList Lib "Wlanapi.dll" ( _
ByVal hClientHandle As Long, pInterfaceGuid As GUID, ByVal dwflags As Long, _
ByVal pReserved As Long, ppAvailableNetworkList As Long) As Long
Declare PtrSafe Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Any, _
Source As Any, ByVal Length As Long)
Declare PtrSafe Sub WlanFreeMemory Lib "Wlanapi.dll" (ByVal pMemory As Long)
Type WiFis
ssid As String: signal As Single
End Type
Public Function GetWiFi() As WiFis()
'returns an array of custom type WiFis (1st interface only)
Dim udtList As WLAN_INTERFACE_INFO_LIST, udtAvailList As WLAN_AVAILABLE_NETWORK_LIST, udtNetwork As WLAN_AVAILABLE_NETWORK
Dim lngReturn As Long, lngHandle As Long, lngVersion As Long, lngList As Long, lngAvailable As Long
Dim lngStart As Long, intCount As Integer, ssid As String, signal As Single, wifiOut() As WiFis
n = 0
lngReturn = WlanOpenHandle(2&, 0&, lngVersion, lngHandle) 'get handle
If lngReturn <> 0 Then
Debug.Print "Couldn't get wlan handle (Code " & lngReturn & ")"
Exit Function
End If
lngReturn = WlanEnumInterfaces(ByVal lngHandle, 0&, lngList) 'enumerate <*first interface only*>
CopyMemory udtList, ByVal lngList, Len(udtList)
lngReturn = WlanGetAvailableNetworkList(lngHandle, udtList.InterfaceInfo.ifGuid, 2&, 0&, lngAvailable) 'get network list
CopyMemory udtAvailList, ByVal lngAvailable, LenB(udtAvailList)
intCount = 0
lngStart = lngAvailable + 8
Do
CopyMemory udtNetwork, ByVal lngStart, Len(udtNetwork) ' Populate avail. network structure
ssid = Replace(StrConv(udtNetwork.dot11Ssid.ucSSID, vbUnicode), Chr(0), "")
If Len(ssid) < 4 Then ssid = "(Unnamed)"
signal = CSng(udtNetwork.wlanSignalQuality) / 100
'[Signal] = 0 to 100 which represents the signal strength (100 Signal)=(-100dBm RSSI), (100 Signal)=(-50dBm RSSI)
If udtNetwork.dwflags = 0 Then
n = n + 1
ReDim Preserve wifiOut(n)
wifiOut(n).ssid = ssid
wifiOut(n).signal = signal
Else
'skipping networks with [dwflags] > 0
'I *think* that's what I'm supposed to do
'Returns 3 for currently connected network, 2 for networks that have profiles
End If
intCount = intCount + 1
lngStart = lngStart + Len(udtNetwork)
Loop Until intCount = udtAvailList.dwNumberOfItems
WlanFreeMemory lngAvailable 'clean up memory
WlanFreeMemory lngList
GetWiFi = wifiOut 'Success! (function is populated with cached network list)
End Function
...and the problem:
Refresh network list using
WlanScan
?
This does not generate a VBA error, but does return code 1168
(which I can't identify)/ (Source)
'Added blindly:'wlanui type library (wlanui.dll) and "wlan pref iua" (wlanconn.dll)
Public Type DOT11_SSID
uSSIDLength As LongPtr: ucSSID As String
End Type
Private Type GUID 'from cpearson.com/excel/CreateGUID.aspx
Data1 As LongPtr: Data2 As Integer
Data3 As Integer: Data4(0 To 7) As Byte
End Type
#If Win64 Then 'also new to Office-64bit, but seems okay
Declare PtrSafe Function WlanScan Lib "Wlanapi.dll" _
(ByVal hClientHandle As LongPtr, ByRef pInterfaceGuid As GUID, _
ByVal pDot11Ssid As LongPtr, ByVal pIeData As LongPtr, _
ByVal pReserved As LongPtr) As LongPtr
#Else
Private Declare WlanScan Lib "Wlanapi.dll" _
(ByVal hClientHandle As LongPtr, ByRef pInterfaceGuid As GUID, _
ByVal pDot11Ssid As LongPtr, ByVal pIeData As LongPtr, _
ByVal pReserved As LongPtr) As LongPtr
#End If
Sub test_RefreshNetworkList()
Dim hresult As LongPtr, phClientHandle As Long, pdwNegotiatedVersion As Long
Dim retVal As Longptr, g As GUID
hresult = WlanOpenHandle(2&, 0&, pdwNegotiatedVersion, phClientHandle)
retVal = WlanScan(phClientHandle, g, 0, 0, 0)
Select Case retVal
Case 87: Debug.Print "ERROR_INVALID_PARAMETER"
Case 6: Debug.Print "ERROR_INVALID_HANDLE"
Case 8: Debug.Print "ERROR_NOT_ENOUGH_MEMORY"
Case Else: Debug.Print "RPC_STATUS : " & retVal ' "misc errors"
End Select
End Sub
Surely there's a roundabout way to refresh the network list from VBA? I'm cool with workarounds that I can automate... anything?!
Thanks!
Edit:
I changed Long
to LongPtr
in the applicable (I think) spots. Same error.
Here's the WlanOpenHandle
and WlanScan
definitions.
Declare PtrSafe Function WlanOpenHandle Lib "Wlanapi.dll"
(ByVal dwClientVersion As LongPtr, _
ByVal pdwReserved As LongPtr,
ByRef pdwNegotiaitedVersion As LongPtr, _
ByRef phClientHandle As LongPtr ) As LongPtr
(...it was also my first attempt time using compiler constants.)
#If Win64 Then
Declare PtrSafe Function WlanScan Lib "Wlanapi.dll" _
(ByVal hClientHandle As LongPtr,
ByRef pInterfaceGuid As GUID, _
ByVal pDot11Ssid As LongPtr,
ByVal pIeData As LongPtr, _
ByVal pReserved As LongPtr) As LongPtr
#Else
Private Declare WlanScan Lib "Wlanapi.dll" _
(ByVal hClientHandle As LongPtr,
ByRef pInterfaceGuid As GUID, _
ByVal pDot11Ssid As LongPtr,
ByVal pIeData As LongPtr, _
ByVal pReserved As LongPtr ) As LongPtr
#End If