Graham Mayor

Option Explicit

Const PRINTER_ENUM_CONNECTIONS = &H4
Const PRINTER_ENUM_LOCAL = &H2

Private Declare Function EnumPrinters Lib "winspool.drv" Alias "EnumPrintersA" _
(ByVal flags As Long, ByVal name As String, ByVal Level As Long, _
pPrinterEnum As Long, ByVal cdBuf As Long, pcbNeeded As Long, _
pcReturned As Long) As Long

Private Declare Function PtrToStr Lib "kernel32" Alias "lstrcpyA" _
(ByVal RetVal As String, ByVal Ptr As Long) As Long

Private Declare Function StrLen Lib "kernel32" Alias "lstrlenA" _
(ByVal Ptr As Long) As Long


Public Function ListPrinters() As Variant

Dim bSuccess As Boolean
Dim iBufferRequired As Long
Dim iBufferSize As Long
Dim iBuffer() As Long
Dim iEntries As Long
Dim iIndex As Long
Dim strPrinterName As String
Dim iDummy As Long
Dim iDriverBuffer() As Long
Dim strPrinters() As String

iBufferSize = 3072

ReDim iBuffer((iBufferSize \ 4) - 1) As Long

'EnumPrinters will return a value False if the buffer is not big enough
bSuccess = EnumPrinters(PRINTER_ENUM_CONNECTIONS Or _
PRINTER_ENUM_LOCAL, vbNullString, _
1, iBuffer(0), iBufferSize, iBufferRequired, iEntries)

If Not bSuccess Then
If iBufferRequired > iBufferSize Then
iBufferSize = iBufferRequired
Debug.Print "iBuffer too small. Trying again with "; _
iBufferSize & " bytes."
ReDim iBuffer(iBufferSize \ 4) As Long
End If
'Try again with new buffer
bSuccess = EnumPrinters(PRINTER_ENUM_CONNECTIONS Or _
PRINTER_ENUM_LOCAL, vbNullString, _
1, iBuffer(0), iBufferSize, iBufferRequired, iEntries)
End If

If Not bSuccess Then
'Enumprinters returned False
MsgBox "Error enumerating printers."
Exit Function
Else
'Enumprinters returned True, use found printers to fill the array
ReDim strPrinters(iEntries - 1)
For iIndex = 0 To iEntries - 1
'Get the printername
strPrinterName = Space$(StrLen(iBuffer(iIndex * 4 + 2)))
iDummy = PtrToStr(strPrinterName, iBuffer(iIndex * 4 + 2))
strPrinters(iIndex) = strPrinterName
Next iIndex
End If

ListPrinters = strPrinters

End Function


'You could call the function as follows:

Sub Test()

Dim StrPrinters As Variant, x As Long

StrPrinters = ListPrinters

'First check whether the array is filled with anything, by calling another function, IsBounded.
If IsBounded(StrPrinters) Then
For x = LBound(strPrinters) To UBound(strPrinters)
Debug.Print StrPrinters(x)
Next x
Else
Debug.Print "No printers found"
End If

End Sub

Public Function IsBounded(vArray As Variant) As Boolean

'If the variant passed to this function is an array, the function will return True;
'otherwise it will return False
On Error Resume Next
IsBounded = IsNumeric(UBound(vArray))

End Function