Convert from \Device\HarddiskVolume1 to C: in vb6 - vb6

Question

Is there any way to convert from \Device\HarddiskVolume1\programfile\explorer.exe to C:\programfile\explorer.exe in visual basic 6?
thanks

Answer 1

Try this
Option Explicit
Private Declare Function QueryDosDevice Lib "kernel32" Alias "QueryDosDeviceA" (ByVal lpDeviceName As String, ByVal lpTargetPath As String, ByVal ucchMax As Long) As Long
Private Sub Command1_Click()
Debug.Print pvReplaceDevice("\Device\HarddiskVolume1\aaa.txt")
End Sub
Private Function pvReplaceDevice(sPath As String) As String
Dim sDrive As String
Dim sDevice As String
Dim lIdx As Long
For lIdx = 0 To 25
sDrive = Chr$(65 + lIdx) & ":"
sDevice = Space(1000)
If QueryDosDevice(sDrive, sDevice, Len(sDevice)) <> 0 Then
sDevice = Left$(sDevice, InStr(sDevice, Chr$(0)) - 1)
' Debug.Print sDrive; "="; sDevice
If LCase$(Left$(sPath, Len(sDevice))) = LCase$(sDevice) Then
pvReplaceDevice = sDrive & Mid$(sPath, Len(sDevice) + 1)
Exit Function
End If
End If
Next
pvReplaceDevice = sPath
End Function

Answer 2

If you want an efficient use of API functions, create a class - "DiskDevice"
Option Explicit
Private Declare Function GetLogicalDriveStrings Lib "Kernel32" Alias "GetLogicalDriveStringsW" ( _
ByVal nBufferLength As Long, _
ByVal lpBuffer As Long _
) As Long
Private Declare Function QueryDosDevice Lib "Kernel32.dll" Alias "QueryDosDeviceW" ( _
ByVal lpDeviceName As Long, _
ByVal lpTargetPath As Long, _
ByVal ucchMax As Long _
) As Long
Private m_colDrivesKeyedByDevice As VBA.Collection
Private Sub Class_Initialize()
Dim sDriveStrings As String
Dim vasDriveStrings As Variant
Dim nIndex As Long
Dim sDrive As String
' Allocate max size buffer [A-Z]:\\\0 and retrieve all drives on the system.
sDriveStrings = Space$(105)
GetLogicalDriveStrings 1000, StrPtr(sDriveStrings)
' Split over the null chars between each substring.
vasDriveStrings = Split(sDriveStrings, vbNullChar)
Set m_colDrivesKeyedByDevice = New VBA.Collection
' Iterate through each drive string (escaping later if any item is null string).
For nIndex = 0 To UBound(vasDriveStrings)
sDrive = Left$(vasDriveStrings(nIndex), 2) ' Ignore the backslash.
If Len(sDrive) = 0 Then
Exit For
End If
' Create mapping from Drive => Device
m_colDrivesKeyedByDevice.Add sDrive, GetDeviceForDrive(sDrive)
Next nIndex
End Sub
' Retrieve the device string \device\XXXXXX for the drive X:
Private Function GetDeviceForDrive(ByRef the_sDrive As String)
Const knBufferLen As Long = 1000
Dim sBuffer As String
Dim nRet As Long
sBuffer = Space$(knBufferLen)
nRet = QueryDosDevice(StrPtr(the_sDrive), StrPtr(sBuffer), knBufferLen)
GetDeviceForDrive = Left$(sBuffer, nRet - 2) ' Ignore 2 terminating null chars.
End Function
Public Function GetFilePathFromDevicePath(ByRef the_sDevicePath As String) As String
Dim nPosSecondBackslash As Long
Dim nPosThirdBackslash As Long
Dim sDevice As String
Dim sDisk As String
' Path is always \Device\<device>\path1\path2\etc. Just get everything before the third backslash.
nPosSecondBackslash = InStr(2, the_sDevicePath, "\")
nPosThirdBackslash = InStr(nPosSecondBackslash + 1, the_sDevicePath, "\")
sDevice = Left(the_sDevicePath, nPosThirdBackslash - 1)
sDisk = m_colDrivesKeyedByDevice.Item(sDevice) ' Lookup
' Reassemble, this time with disk.
GetFilePathFromDevicePath = sDisk & Mid$(the_sDevicePath, nPosThirdBackslash)
End Function
Now, you use code like:
Set m_oDiskDevice = New DiskDevice
...
sMyPath = m_oDiskDevice.GetFilePathFromDevicePath("\Device\HarddiskVolume1\programfile\explorer.exe")
That way you don't have to call the API functions multiple times - you just do a collection lookup.