EnumJobs返回作业个数老是为0？？

[north00]

各位高手，在VBA中使用EnumJobs监控网络打印机，结果发现返回作业的个数老为0，但是这个函数本身返回值为1，也就是意味着连接上打印机了，代码如下：

Private Sub CommandButton1_Click()
    
    Dim sPrintName1 As String
    Dim hPrinter As Long
    Dim pDefault As PRINTER_DEFAULTS
    
    Dim lngJobsFirstJob As Long, lngJobsEnumJob As Long, lngJobsLevel As Long
    Dim byteJobsBuffer() As Byte
    Dim lngJobsNeeded As Long
    Dim lngJobsReturned As Long
    Dim lngResult As Long
    Dim udtJobInfo1() As JOB_INFO_1
    
    Dim byteBuffer(64) As Byte
    
    On Error Resume Next
    
    sPrintName1 = "FX DocuCentre-IV C2265 PCL 6 (B8#2F)"
    
    lngResult = OpenPrinter(sPrintName1, hPrinter, pDefault)
    
    lngJobsFirstJob = 0 ' zero-based position within the print queue of the first print job to enumerate
    lngJobsEnumJob = 99 ' total number of print jobs to enumerate
    
    lngJobsLevel = 1    ' Specifies whether the function should use JOB_INFO_1
                        ' or JOB_INFO_2 structures to store data for the enumerated jobs
    
    lngResult = EnumJobs(hPrinter, lngJobsFirstJob, lngJobsEnumJob, lngJobsLevel, ByVal 0&, 0, lngJobsNeeded, lngJobsReturned)
    
    If lngJobsNeeded > 0 Then
        MsgBox lngJobsReturned
        ReDim byteJobsBuffer(lngJobsNeeded - 1)
        ReDim udtJobInfo1(lngJobsNeeded - 1)
        
        lngResult = EnumJobs(hPrinter, lngJobsFirstJob, lngJobsEnumJob, _
                         lngJobsLevel, byteJobsBuffer(0), lngJobsNeeded, _
                         lngJobsNeeded, lngJobsReturned)
                         
        If lngJobsReturned > 0 Then
            
            MoveMemory udtJobInfo1(0), byteJobsBuffer(0), Len(udtJobInfo1(0)) * lngJobsReturned
            
            For lngjobscount = 0 To lngJobsReturned - 1
                
                With udtJobInfo1(lngjobscount)
                  
                ' Get the document name
                  lngResult = lstrcpy(byteBuffer(0), ByVal .pDocument)
                  
                  strDocument = StrConv(byteBuffer(), vbUnicode)
                  ' Document name has been returned as null terminated-string
                  strDocument = Left$(strDocument, InStr(strDocument, vbNullChar) - 1)
                  
                  Sheet1.Range("D" & lngjobscount + 2) = strDocument
                  
                  
                ' Get the document's owner name
                  lngResult = lstrcpy(byteBuffer(0), ByVal .pUserName)
                  
                  strOwnerName = StrConv(byteBuffer(), vbUnicode)
                  ' Document's owner name has been returned as null-terminated string
                  strOwnerName = Left$(strOwnerName, InStr(strOwnerName, vbNullChar) - 1)
                  
                  Sheet1.Range("C" & lngjobscount + 2) = strOwnerName
                  
                                 
                End With
                
            Next lngjobscount
            
        Else
            ' number of jobs returned = 0 (no jobs)
            lngjobscount = 0
      
        End If
        
    End If
    
    lngResult = ClosePrinter(hPrinter)
    
    
End Sub