[RESOLVED] PrintDlgEx API failed to return full name of printer

[Jonney]

I used Krool's OpenPrinterEx function in CommonDialog class. The function failed to return the full name of the chosen printer. The printer name is "\\192.4.4.143\Canon iR2002/2202 UFRII LT(1)" showing on the Printer Dialog. But I watched the return printer name (NewPrinterName) is "\\192.4.4.143\Canon iR2002/220" which is 30 characters length. what is the reason?

When a Microsoft Windows application prints, it must identify the target printer by its full name. The DEVMODE structure that was introduced in 16-bit Windows version 3.1 has a limitation of 32 characters for a printer name. However, printer names in Win32 operating systems can be much longer.

Look like the string is being truncated. I tried to changed CCHDEVICENAME =32 to 128 to increase the buffer but still no luck. Maybe the DMDeviceName in DEVMODE structure should be defined to Pointer?

Private Type PRINTDLGEX
    lStructSize As Long
    hWndOwner As Long
    hDevMode As Long
    hDevNames As Long
    hDC As Long
    Flags As Long
    Flags2 As Long
    ExclusionFlags As Long
    nPageRanges As Long
    nMaxPageRanges As Long
    lpPageRanges As Long
    nMinPage As Long
    nMaxPage As Long
    nCopies As Long
    hInstance As Long
    lpPrintTemplateName As Long
    lpCallback As Long
    nPropertyPages As Long
    lphPropertyPages As Long
    nStartPage As Long
    dwResultAction As Long
End Type

Private Const CCHDEVNAMESEXTRA As Long = 100
Private Type DEVNAMES
    wDriverOffset As Integer
    wDeviceOffset As Integer
    wOutputOffset As Integer
    wDefault As Integer
    wExtra(0 To ((CCHDEVNAMESEXTRA * 2) - 1)) As Byte
End Type
Private Const CCHDEVICENAME As Long = 128 '32
Private Const CCHFORMNAME As Long = 32
Private Const DM_ORIENTATION As Long = &H1
Private Const DM_PAPERSIZE As Long = &H2
Private Const DM_COPIES As Long = &H100
Private Const DM_DEFAULTSOURCE As Long = &H200
Private Const DM_PRINTQUALITY As Long = &H400
Private Const DM_COLOR As Long = &H800
Private Const DM_DUPLEX As Long = &H1000
Private Const DM_COLLATE As Long = &H8000&
Private Type DEVMODE
    DMDeviceName(0 To ((CCHDEVICENAME * 2) - 1)) As Byte
    DMSpecVersion As Integer
    DMDriverVersion As Integer
    DMSize As Integer
    DMDriverExtra As Integer
    DMFields As Long
    DMOrientation As Integer
    DMPaperSize As Integer
    DMPaperLength As Integer
    DMPaperWidth As Integer
    DMScale As Integer
    DMCopies As Integer
    DMDefaultSource As Integer
    DMPrintQuality As Integer
    DMColor As Integer
    DMDuplex As Integer
    DMYResolution As Integer
    DMTTOption As Integer
    DMCollate As Integer
    DMFormName(0 To ((CCHFORMNAME * 2) - 1)) As Byte
    DMLogPixels As Integer
    DMBitsPerPel As Long
    DMPelsWidth As Long
    DMPelsHeight As Long
    DMDisplayFlags As Long
    DMDisplayFrequency As Long
    DMICMMethod As Long
    DMICMIntent As Long
    DMMediaType As Long
    DMDitherType As Long
    DMReserved1 As Long
    DMReserved2 As Long
    DMPanningWidth As Long
    DMPanningHeight As Long
End Type

Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (ByRef Destination As Any, ByRef Source As Any, ByVal Length As Long)
Private Declare Function GlobalLock Lib "kernel32" (ByVal hMem As Long) As Long
Private Declare Function GlobalUnlock Lib "kernel32" (ByVal hMem As Long) As Long
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 Function PrintDialogEx Lib "comdlg32" Alias "PrintDlgExW" (ByRef lpPrintDlgEx As PRINTDLGEX) As Long

Private PropFlags As Long
Private PropMin As Long, PropMax As Long
Private PropFromPage As Long, PropToPage As Long
Private PropPrinterDefault As Boolean

Public Function ShowPrinterEx() As CdlPDResultConstants
Dim PDLGEX As PRINTDLGEX, PPAGERANGE As PRINTPAGERANGE, DMODE As DEVMODE, DNAMES As DEVNAMES
Dim lpDevMode As Long, lpDevNames As Long
Dim ObjPrinter As VB.Printer, NewPrinterName As String, Buffer As String
With PDLGEX
.lStructSize = LenB(PDLGEX)
If Not Screen.ActiveForm Is Nothing Then
    .hWndOwner = Screen.ActiveForm.hWnd
Else
    .hWndOwner = GetActiveWindow()
End If
.Flags = PropFlags
.nPageRanges = 1
.nMaxPageRanges = 1
PPAGERANGE.nFromPage = PropFromPage
PPAGERANGE.nToPage = PropToPage
.nMinPage = PropMin
.nMaxPage = PropMax
.lpPageRanges = VarPtr(PPAGERANGE)
Const START_PAGE_GENERAL As Long = &HFFFFFFFF
.nStartPage = START_PAGE_GENERAL
End With
If VB.Printers.Count > 0 And (PDLGEX.Flags And CdlPDReturnDefault) = 0 Then
    With VB.Printer
    DMODE.DMSize = LenB(DMODE)
    Buffer = Left$(.DeviceName, CCHDEVICENAME)
    CopyMemory DMODE.DMDeviceName(0), ByVal StrPtr(Buffer), LenB(Buffer)
    DMODE.DMFields = DM_ORIENTATION Or DM_PAPERSIZE Or DM_COPIES Or DM_DEFAULTSOURCE Or DM_PRINTQUALITY Or DM_COLOR Or DM_DUPLEX Or DM_COLLATE
    DMODE.DMOrientation = .Orientation
    DMODE.DMPaperSize = .PaperSize
    DMODE.DMCopies = .Copies
    DMODE.DMDefaultSource = .PaperBin
    DMODE.DMPrintQuality = .PrintQuality
    DMODE.DMColor = .ColorMode
    DMODE.DMDuplex = .Duplex
    DMODE.DMCollate = IIf((PDLGEX.Flags And CdlPDCollate) <> 0, 1, 0)
    DNAMES.wDriverOffset = 4
    DNAMES.wDeviceOffset = DNAMES.wDriverOffset + Len(.DriverName) + 1
    DNAMES.wOutputOffset = DNAMES.wDeviceOffset + Len(.DeviceName) + 1
    DNAMES.wDefault = 0
    Buffer = Left$(.DriverName & vbNullChar & .DeviceName & vbNullChar & .Port & vbNullChar, CCHDEVNAMESEXTRA)
    CopyMemory DNAMES.wExtra(0), ByVal StrPtr(Buffer), LenB(Buffer)
    PDLGEX.nCopies = .Copies
    PDLGEX.hDevMode = GlobalAlloc(GMEM_MOVEABLE Or GMEM_ZEROINIT, LenB(DMODE))
    lpDevMode = GlobalLock(PDLGEX.hDevMode)
    CopyMemory ByVal lpDevMode, DMODE, LenB(DMODE)
    GlobalUnlock PDLGEX.hDevMode
    PDLGEX.hDevNames = GlobalAlloc(GMEM_MOVEABLE Or GMEM_ZEROINIT, LenB(DNAMES))
    lpDevNames = GlobalLock(PDLGEX.hDevNames)
    CopyMemory ByVal lpDevNames, DNAMES, LenB(DNAMES)
    GlobalUnlock PDLGEX.hDevNames
    End With
End If
Dim ErrVal As Long
If PropHookEvents = False Then
    ErrVal = PrintDialogEx(PDLGEX)
Else
    Call ComCtlsCdlPDEXSetHook(Me)
    ErrVal = PrintDialogEx(PDLGEX)
    Call ComCtlsCdlPDEXRemoveHook
End If
If ErrVal = S_OK Then
    If PDLGEX.dwResultAction <> CdlPDResultCancel Then
        lpDevMode = GlobalLock(PDLGEX.hDevMode)
        CopyMemory DMODE, ByVal lpDevMode, LenB(DMODE)
        GlobalUnlock PDLGEX.hDevMode
        GlobalFree PDLGEX.hDevMode
        lpDevNames = GlobalLock(PDLGEX.hDevNames)
        CopyMemory DNAMES, ByVal lpDevNames, LenB(DNAMES)
        GlobalUnlock PDLGEX.hDevNames
        GlobalFree PDLGEX.hDevNames
        NewPrinterName = Left$(DMODE.DMDeviceName(), InStr(DMODE.DMDeviceName(), vbNullChar) - 1)
        Dim PrinterFound As Boolean
        If StrComp(VB.Printer.DeviceName, NewPrinterName, vbTextCompare) <> 0 Then
            For Each ObjPrinter In VB.Printers
                If StrComp(ObjPrinter.DeviceName, NewPrinterName, vbTextCompare) = 0 Then
                    Set VB.Printer = ObjPrinter
                    PrinterFound = True
                    Exit For
                End If
            Next ObjPrinter
        Else
            PrinterFound = True
        End If
        If PropPrinterDefault = True Then Call SetPrinterDefault(NewPrinterName)
        If PrinterFound = True Then
            On Error Resume Next
            With VB.Printer
            .Copies = DMODE.DMCopies
            .Duplex = DMODE.DMDuplex
            .Orientation = DMODE.DMOrientation
            .PaperSize = DMODE.DMPaperSize
            .PrintQuality = DMODE.DMPrintQuality
            .ColorMode = DMODE.DMColor
            .PaperBin = DMODE.DMDefaultSource
            End With
            On Error GoTo 0
        End If
        PropFlags = PDLGEX.Flags
        If (PropFlags And CdlPDUseDevModeCopiesAndCollate) <> 0 Then
            If DMODE.DMCollate = 1 And (PropFlags And CdlPDCollate) = 0 Then PropFlags = PropFlags Or CdlPDCollate
        End If
        PropFromPage = PPAGERANGE.nFromPage
        PropToPage = PPAGERANGE.nToPage
        PropMin = PDLGEX.nMinPage
        PropMax = PDLGEX.nMaxPage
        If (PropFlags And (CdlPDReturnDC Or CdlPDReturnIC)) <> 0 Then PropDC = PDLGEX.hDC
        ShowPrinterEx = PDLGEX.dwResultAction
    Else
        If PropCancelError = True Then Err.Raise Number:=CdlCancel, Description:="Cancel was selected."
    End If
Else
    If PDLGEX.hDevMode <> 0 Then GlobalFree PDLGEX.hDevMode
    If PDLGEX.hDevNames <> 0 Then GlobalFree PDLGEX.hDevNames
    Const E_OUTOFMEMORY As Long = &H8007000E, E_INVALIDARG As Long = &H80070057, E_POINTER As Long = &H80004003, E_HANDLE As Long = &H80070006, E_FAIL As Long = &H80004005
    Select Case ErrVal
        Case E_OUTOFMEMORY, E_INVALIDARG, E_POINTER, E_HANDLE, E_FAIL
            Err.Raise Number:=CdlInitFailure, Description:="The PrintDlgEx function failed during initialization."
        Case Else
            Err.Raise Number:=ErrVal, Description:="Unexpected error."
    End Select
End If
End Function