继续 莫名其妙的问题Printers.Count  ，今天上班，接着研究这个问题，发现调用API函数OK

[quote]

 Private Const PRINTER_ENUM_CONNECTIONS = &H4
 Private Const PRINTER_ENUM_LOCAL = &H2
Private Type PRINTER_INFO_1
         flags As Long
         pDescription As String
         PName As String
         PComment As String
      End Type
 Private Type PRINTER_INFO_4
         pPrinterName As String
         pServerName As String
         Attributes As Long
      End Type
 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
      Sub EnumeratePrinters1()
      Dim Success As Boolean, cbRequired As Long, cbBuffer As Long
      Dim Buffer() As Long, nEntries As Long
      Dim I As Long, PFlags As Long, PDesc As String, PName As String
      Dim PComment As String, Temp As Long
         cbBuffer = 3072
         ReDim Buffer((cbBuffer \\ 4) – 1) As Long
         Success = EnumPrinters(PRINTER_ENUM_CONNECTIONS Or _
                               PRINTER_ENUM_LOCAL, _
                               vbNullString, _
                               1, _
                               Buffer(0), _
                               cbBuffer, _
                               cbRequired, _
                               nEntries)
         If Success Thenwww.yippeesoft.com
            If cbRequired > cbBuffer Then
               cbBuffer = cbRequired
               Debug.Print "Buffer too small.  Trying again with " & _
                        cbBuffer & " bytes."
               ReDim Buffer(cbBuffer \\ 4) As Long
               Success = EnumPrinters(PRINTER_ENUM_CONNECTIONS Or _
                                   PRINTER_ENUM_LOCAL, _
                                   vbNullString, _
                                   1, _
                                   Buffer(0), _
                                   cbBuffer, _
                                   cbRequired, _
                                   nEntries)
               If Not Success Then
                  Debug.Print "Error enumerating printers."
                  Exit Sub
               End If
            End If
         Debug.Print "There are " & nEntries & _
                      " local and connected printers."
         For I = 0 To nEntries – 1
            PFlags = Buffer(4 * I)
            PDesc = Space$(StrLen(Buffer(I * 4 + 1)))
            Temp = PtrToStr(PDesc, Buffer(I * 4 + 1))
            PName = Space$(StrLen(Buffer(I * 4 + 2)))
            Temp = PtrToStr(PName, Buffer(I * 4 + 2))
            PComment = Space$(StrLen(Buffer(I * 4 + 2)))
            Temp = PtrToStr(PComment, Buffer(I * 4 + 2))
            Debug.Print PFlags, PDesc, PName, PComment
         Next I
         Else
            Debug.Print "Error enumerating printers."
         End If
      End Sub
      Sub EnumeratePrinters4()
      Dim Success As Boolean, cbRequired As Long, cbBuffer As Long
      Dim Buffer() As Long, nEntries As Long
      Dim I As Long, PName As String, SName As String
      Dim Attrib As Long, Temp As Long
         cbBuffer = 3072www.yippeesoft.com
         ReDim Buffer((cbBuffer \\ 4) – 1) As Long
         Success = EnumPrinters(PRINTER_ENUM_CONNECTIONS Or _
                               PRINTER_ENUM_LOCAL, _
                               vbNullString, _
                               4, _
                               Buffer(0), _
                               cbBuffer, _
                               cbRequired, _
                               nEntries)
         If Success Thenwww.yippeesoft.com
            If cbRequired > cbBuffer Then
               cbBuffer = cbRequired
               Debug.Print "Buffer too small.  Trying again with " & _
                        cbBuffer & " bytes."
               ReDim Buffer(cbBuffer \\ 4) As Long
               Success = EnumPrinters(PRINTER_ENUM_CONNECTIONS Or _
                                   PRINTER_ENUM_LOCAL, _
                                   vbNullString, _
                                   4, _
                                   Buffer(0), _
                                   cbBuffer, _
                                   cbRequired, _
                                   nEntries)
               If Not Success Then
                  Debug.Print "Error enumerating printers."
                  Exit Sub
               End If
            End Ifwww.yippeesoft.com
            Debug.Print "There are " & nEntries & _
                      " local and connected printers."
            For I = 0 To nEntries – 1
            PName = Space$(StrLen(Buffer(I * 3)))
            Temp = PtrToStr(PName, Buffer(I * 3))
            SName = Space$(StrLen(Buffer(I * 3 + 1)))
            Temp = PtrToStr(SName, Buffer(I * 3 + 1))
            Attrib = Buffer(I * 3 + 2)
            MsgBox "Printer: " & PName \’ + "Server: " & Str(SName) + "Attributes: " & Str(Hex$(Attrib))
            Next I
         Else
            MsgBox "Error enumerating printers."
         End If
      End Sub
[/quote]

难道要我把那一块代码改为API函数？

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