Ause dem API-Guide
31.07.2003 15:32:04
M;ichael Scheffler
Option Explicit
' Get information about all of the local printers using structure 1. Note how
' the elements of the array are loaded into an array of data structures manually. Also
' note how the following special declares must be used to allow numeric string pointers
' to be used in place of strings:
Private Declare Function lstrcpy Lib "kernel32.dll" Alias "lstrcpyA" (ByVal lpString1 As String, ByVal lpString2 As Long) As Long
Private Declare Function lstrlen Lib "kernel32.dll" Alias "lstrlenA" (ByVal lpString As Long) As Long
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
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 Sub Printers()
'KPD-Team 1999
'URL: http://www.allapi.net/
'E-Mail: KPDTeam@Allapi.net
Dim longbuffer() As Long ' resizable array receives information from the function
Dim printinfo() As PRINTER_INFO_1 ' values inside longbuffer() will be put into here
Dim numbytes As Long ' size in bytes of longbuffer()
Dim numneeded As Long ' receives number of bytes necessary if longbuffer() is too small
Dim numprinters As Long ' receives number of printers found
Dim c As Integer, retval As Long ' counter variable & return value
' Get information about the local printers
numbytes = 3076 ' should be sufficiently big, but it may not be
ReDim longbuffer(0 To numbytes / 4) As Long ' resize array -- note how 1 Long = 4 bytes
retval = EnumPrinters(PRINTER_ENUM_LOCAL, "", 1, longbuffer(0), numbytes, numneeded, numprinters)
If retval = 0 Then ' try enlarging longbuffer() to receive all necessary information
numbytes = numneeded
ReDim longbuffer(0 To numbytes / 4) As Long ' make it large enough
retval = EnumPrinters(PRINTER_ENUM_LOCAL, "", 1, longbuffer(0), numbytes, numneeded, numprinters)
If retval = 0 Then ' failed again!
Debug.Print "Could not successfully enumerate the printes."
End ' abort program
End If
End If
' Convert longbuffer() data into printinfo()
If numprinters <> 0 Then ReDim printinfo(0 To numprinters - 1) As PRINTER_INFO_1 ' room for each printer
For c = 0 To numprinters - 1 ' loop, putting each set of information into each element
' longbuffer(4 * c) = .flags, longbuffer(4 * c + 1) = .pDescription, etc.
' For each string, the string is first buffered to provide enough room, and then the string is copied.
printinfo(c).flags = longbuffer(4 * c)
printinfo(c).pDescription = Space(lstrlen(longbuffer(4 * c + 1)))
retval = lstrcpy(printinfo(c).pDescription, longbuffer(4 * c + 1))
printinfo(c).pName = Space(lstrlen(longbuffer(4 * c + 2)))
retval = lstrcpy(printinfo(c).pName, longbuffer(4 * c + 2))
printinfo(c).pComment = Space(lstrlen(longbuffer(4 * c + 3)))
retval = lstrcpy(printinfo(c).pComment, longbuffer(4 * c + 3))
Next c
' Display name of each printer
For c = 0 To numprinters - 1
Debug.Print "Name of printer"; c + 1; " is: "; printinfo(c).pName
Next c
End Sub