在中型和大型企业的任何时候,可能有多个打印机由于纸塞、缺纸或其他一些问题而无法工作。 Microsoft .NET Framework API 中公开的丰富打印机属性集提供了一种快速调查打印机状态的方法。
示例:
创建此类实用工具的主要步骤如下。
获取所有打印服务器的列表。
遍历服务器以查询其打印队列。
在服务器循环的每一轮中,循环检查服务器的每个队列,读取可能指示队列当前不工作的每个属性。
下面的代码是一系列代码片段。 为简单起见,此示例假定有一个以 CRLF 分隔的打印服务器列表。
fileOfPrintServers
变量是StreamReader此文件的对象。 由于每个服务器名称都位于各自的行上,任何对 ReadLine 的调用都会获取下一个服务器的名称,并将 StreamReader 的游标移动到下一行的开头。
在外部循环中,代码为最新的打印服务器创建一个 PrintServer 对象,并指定应用程序对服务器具有管理权限。
注释
如果有大量服务器,可以使用仅初始化所需属性的构造函数来提高性能 PrintServer(String, String[], PrintSystemDesiredAccess) 。
然后,示例使用 GetPrintQueues 创建服务器所有队列的集合,并开始循环遍历这些队列。 此内部循环包含对应于检查打印机状态的两种方式的分支结构:
可以读取QueueStatus属性的标志,该属性是PrintQueueStatus类型。
可以读取每个相关属性,例如 IsOutOfPaper,和 IsPaperJammed。
此示例演示了这两种方法,因此用户之前已经被提示使用哪种方法,并回应“y”来表示他们想使用属性的QueueStatus标志。 有关这两种方法的详细信息,请参阅下文。
最后,结果将呈现给用户。
// Survey queue status for every queue on every print server
System::String^ line;
System::String^ statusReport = "\n\nAny problem states are indicated below:\n\n";
while ((line = fileOfPrintServers->ReadLine()) != nullptr)
{
System::Printing::PrintServer^ myPS = gcnew System::Printing::PrintServer(line, PrintSystemDesiredAccess::AdministrateServer);
System::Printing::PrintQueueCollection^ myPrintQueues = myPS->GetPrintQueues();
statusReport = statusReport + "\n" + line;
for each (System::Printing::PrintQueue^ pq in myPrintQueues)
{
pq->Refresh();
statusReport = statusReport + "\n\t" + pq->Name + ":";
if (useAttributesResponse == "y")
{
TroubleSpotter::SpotTroubleUsingQueueAttributes(statusReport, pq);
// TroubleSpotter class is defined in the complete example.
} else
{
TroubleSpotter::SpotTroubleUsingProperties(statusReport, pq);
}
}
}
fileOfPrintServers->Close();
Console::WriteLine(statusReport);
Console::WriteLine("\nPress Return to continue.");
Console::ReadLine();
// Survey queue status for every queue on every print server
String line;
String statusReport = "\n\nAny problem states are indicated below:\n\n";
while ((line = fileOfPrintServers.ReadLine()) != null)
{
PrintServer myPS = new PrintServer(line, PrintSystemDesiredAccess.AdministrateServer);
PrintQueueCollection myPrintQueues = myPS.GetPrintQueues();
statusReport = statusReport + "\n" + line;
foreach (PrintQueue pq in myPrintQueues)
{
pq.Refresh();
statusReport = statusReport + "\n\t" + pq.Name + ":";
if (useAttributesResponse == "y")
{
TroubleSpotter.SpotTroubleUsingQueueAttributes(ref statusReport, pq);
// TroubleSpotter class is defined in the complete example.
}
else
{
TroubleSpotter.SpotTroubleUsingProperties(ref statusReport, pq);
}
}// end for each print queue
}// end while list of print servers is not yet exhausted
fileOfPrintServers.Close();
Console.WriteLine(statusReport);
Console.WriteLine("\nPress Return to continue.");
Console.ReadLine();
' Survey queue status for every queue on every print server
Dim line As String
Dim statusReport As String = vbLf & vbLf & "Any problem states are indicated below:" & vbLf & vbLf
line = fileOfPrintServers.ReadLine()
Do While line IsNot Nothing
Dim myPS As New PrintServer(line, PrintSystemDesiredAccess.AdministrateServer)
Dim myPrintQueues As PrintQueueCollection = myPS.GetPrintQueues()
statusReport = statusReport & vbLf & line
For Each pq As PrintQueue In myPrintQueues
pq.Refresh()
statusReport = statusReport & vbLf & vbTab & pq.Name & ":"
If useAttributesResponse = "y" Then
TroubleSpotter.SpotTroubleUsingQueueAttributes(statusReport, pq)
' TroubleSpotter class is defined in the complete example.
Else
TroubleSpotter.SpotTroubleUsingProperties(statusReport, pq)
End If
Next pq ' end for each print queue
line = fileOfPrintServers.ReadLine()
Loop ' end while list of print servers is not yet exhausted
fileOfPrintServers.Close()
Console.WriteLine(statusReport)
Console.WriteLine(vbLf & "Press Return to continue.")
Console.ReadLine()
若要使用属性的 QueueStatus 标志检查打印机状态,请检查每个相关标志,以查看是否已设置它。 要检查一组位标志中是否设置了某个位的标准方法是使用这组标志作为一个操作数,与另一操作数中的该标志本身执行逻辑 AND运算。 由于标志本身只设置了一个位,因此逻辑 AND 的结果最多就是设置了同一位。 若要了解它是否是,只需将逻辑 AND 的结果与标志本身进行比较。 有关详细信息,请参阅PrintQueueStatus、和运算符(C# 参考)和FlagsAttribute。
对于其位已设定的每个属性,代码会将提示添加到最终呈现给用户的报告中。 (下面讨论了在代码末尾调用的 ReportAvailabilityAtThisTime 方法。
internal:
// Check for possible trouble states of a printer using the flags of the QueueStatus property
static void SpotTroubleUsingQueueAttributes (System::String^% statusReport, System::Printing::PrintQueue^ pq)
{
if ((pq->QueueStatus & PrintQueueStatus::PaperProblem) == PrintQueueStatus::PaperProblem)
{
statusReport = statusReport + "Has a paper problem. ";
}
if ((pq->QueueStatus & PrintQueueStatus::NoToner) == PrintQueueStatus::NoToner)
{
statusReport = statusReport + "Is out of toner. ";
}
if ((pq->QueueStatus & PrintQueueStatus::DoorOpen) == PrintQueueStatus::DoorOpen)
{
statusReport = statusReport + "Has an open door. ";
}
if ((pq->QueueStatus & PrintQueueStatus::Error) == PrintQueueStatus::Error)
{
statusReport = statusReport + "Is in an error state. ";
}
if ((pq->QueueStatus & PrintQueueStatus::NotAvailable) == PrintQueueStatus::NotAvailable)
{
statusReport = statusReport + "Is not available. ";
}
if ((pq->QueueStatus & PrintQueueStatus::Offline) == PrintQueueStatus::Offline)
{
statusReport = statusReport + "Is off line. ";
}
if ((pq->QueueStatus & PrintQueueStatus::OutOfMemory) == PrintQueueStatus::OutOfMemory)
{
statusReport = statusReport + "Is out of memory. ";
}
if ((pq->QueueStatus & PrintQueueStatus::PaperOut) == PrintQueueStatus::PaperOut)
{
statusReport = statusReport + "Is out of paper. ";
}
if ((pq->QueueStatus & PrintQueueStatus::OutputBinFull) == PrintQueueStatus::OutputBinFull)
{
statusReport = statusReport + "Has a full output bin. ";
}
if ((pq->QueueStatus & PrintQueueStatus::PaperJam) == PrintQueueStatus::PaperJam)
{
statusReport = statusReport + "Has a paper jam. ";
}
if ((pq->QueueStatus & PrintQueueStatus::Paused) == PrintQueueStatus::Paused)
{
statusReport = statusReport + "Is paused. ";
}
if ((pq->QueueStatus & PrintQueueStatus::TonerLow) == PrintQueueStatus::TonerLow)
{
statusReport = statusReport + "Is low on toner. ";
}
if ((pq->QueueStatus & PrintQueueStatus::UserIntervention) == PrintQueueStatus::UserIntervention)
{
statusReport = statusReport + "Needs user intervention. ";
}
// Check if queue is even available at this time of day
// The method below is defined in the complete example.
ReportAvailabilityAtThisTime(statusReport, pq);
};
// Check for possible trouble states of a printer using the flags of the QueueStatus property
internal static void SpotTroubleUsingQueueAttributes(ref String statusReport, PrintQueue pq)
{
if ((pq.QueueStatus & PrintQueueStatus.PaperProblem) == PrintQueueStatus.PaperProblem)
{
statusReport = statusReport + "Has a paper problem. ";
}
if ((pq.QueueStatus & PrintQueueStatus.NoToner) == PrintQueueStatus.NoToner)
{
statusReport = statusReport + "Is out of toner. ";
}
if ((pq.QueueStatus & PrintQueueStatus.DoorOpen) == PrintQueueStatus.DoorOpen)
{
statusReport = statusReport + "Has an open door. ";
}
if ((pq.QueueStatus & PrintQueueStatus.Error) == PrintQueueStatus.Error)
{
statusReport = statusReport + "Is in an error state. ";
}
if ((pq.QueueStatus & PrintQueueStatus.NotAvailable) == PrintQueueStatus.NotAvailable)
{
statusReport = statusReport + "Is not available. ";
}
if ((pq.QueueStatus & PrintQueueStatus.Offline) == PrintQueueStatus.Offline)
{
statusReport = statusReport + "Is off line. ";
}
if ((pq.QueueStatus & PrintQueueStatus.OutOfMemory) == PrintQueueStatus.OutOfMemory)
{
statusReport = statusReport + "Is out of memory. ";
}
if ((pq.QueueStatus & PrintQueueStatus.PaperOut) == PrintQueueStatus.PaperOut)
{
statusReport = statusReport + "Is out of paper. ";
}
if ((pq.QueueStatus & PrintQueueStatus.OutputBinFull) == PrintQueueStatus.OutputBinFull)
{
statusReport = statusReport + "Has a full output bin. ";
}
if ((pq.QueueStatus & PrintQueueStatus.PaperJam) == PrintQueueStatus.PaperJam)
{
statusReport = statusReport + "Has a paper jam. ";
}
if ((pq.QueueStatus & PrintQueueStatus.Paused) == PrintQueueStatus.Paused)
{
statusReport = statusReport + "Is paused. ";
}
if ((pq.QueueStatus & PrintQueueStatus.TonerLow) == PrintQueueStatus.TonerLow)
{
statusReport = statusReport + "Is low on toner. ";
}
if ((pq.QueueStatus & PrintQueueStatus.UserIntervention) == PrintQueueStatus.UserIntervention)
{
statusReport = statusReport + "Needs user intervention. ";
}
// Check if queue is even available at this time of day
// The method below is defined in the complete example.
ReportAvailabilityAtThisTime(ref statusReport, pq);
}
' Check for possible trouble states of a printer using the flags of the QueueStatus property
Friend Shared Sub SpotTroubleUsingQueueAttributes(ByRef statusReport As String, ByVal pq As PrintQueue)
If (pq.QueueStatus And PrintQueueStatus.PaperProblem) = PrintQueueStatus.PaperProblem Then
statusReport = statusReport & "Has a paper problem. "
End If
If (pq.QueueStatus And PrintQueueStatus.NoToner) = PrintQueueStatus.NoToner Then
statusReport = statusReport & "Is out of toner. "
End If
If (pq.QueueStatus And PrintQueueStatus.DoorOpen) = PrintQueueStatus.DoorOpen Then
statusReport = statusReport & "Has an open door. "
End If
If (pq.QueueStatus And PrintQueueStatus.Error) = PrintQueueStatus.Error Then
statusReport = statusReport & "Is in an error state. "
End If
If (pq.QueueStatus And PrintQueueStatus.NotAvailable) = PrintQueueStatus.NotAvailable Then
statusReport = statusReport & "Is not available. "
End If
If (pq.QueueStatus And PrintQueueStatus.Offline) = PrintQueueStatus.Offline Then
statusReport = statusReport & "Is off line. "
End If
If (pq.QueueStatus And PrintQueueStatus.OutOfMemory) = PrintQueueStatus.OutOfMemory Then
statusReport = statusReport & "Is out of memory. "
End If
If (pq.QueueStatus And PrintQueueStatus.PaperOut) = PrintQueueStatus.PaperOut Then
statusReport = statusReport & "Is out of paper. "
End If
If (pq.QueueStatus And PrintQueueStatus.OutputBinFull) = PrintQueueStatus.OutputBinFull Then
statusReport = statusReport & "Has a full output bin. "
End If
If (pq.QueueStatus And PrintQueueStatus.PaperJam) = PrintQueueStatus.PaperJam Then
statusReport = statusReport & "Has a paper jam. "
End If
If (pq.QueueStatus And PrintQueueStatus.Paused) = PrintQueueStatus.Paused Then
statusReport = statusReport & "Is paused. "
End If
If (pq.QueueStatus And PrintQueueStatus.TonerLow) = PrintQueueStatus.TonerLow Then
statusReport = statusReport & "Is low on toner. "
End If
If (pq.QueueStatus And PrintQueueStatus.UserIntervention) = PrintQueueStatus.UserIntervention Then
statusReport = statusReport & "Needs user intervention. "
End If
' Check if queue is even available at this time of day
' The method below is defined in the complete example.
ReportAvailabilityAtThisTime(statusReport, pq)
End Sub
若要使用每个属性检查打印机状态,只需读取每个属性,并在最终报告中添加注释。如果属性为true
,则将该报告展示给用户。 (下面讨论了在代码末尾调用的 ReportAvailabilityAtThisTime 方法。
internal:
// Check for possible trouble states of a printer using its properties
static void SpotTroubleUsingProperties (System::String^% statusReport, System::Printing::PrintQueue^ pq)
{
if (pq->HasPaperProblem)
{
statusReport = statusReport + "Has a paper problem. ";
}
if (!(pq->HasToner))
{
statusReport = statusReport + "Is out of toner. ";
}
if (pq->IsDoorOpened)
{
statusReport = statusReport + "Has an open door. ";
}
if (pq->IsInError)
{
statusReport = statusReport + "Is in an error state. ";
}
if (pq->IsNotAvailable)
{
statusReport = statusReport + "Is not available. ";
}
if (pq->IsOffline)
{
statusReport = statusReport + "Is off line. ";
}
if (pq->IsOutOfMemory)
{
statusReport = statusReport + "Is out of memory. ";
}
if (pq->IsOutOfPaper)
{
statusReport = statusReport + "Is out of paper. ";
}
if (pq->IsOutputBinFull)
{
statusReport = statusReport + "Has a full output bin. ";
}
if (pq->IsPaperJammed)
{
statusReport = statusReport + "Has a paper jam. ";
}
if (pq->IsPaused)
{
statusReport = statusReport + "Is paused. ";
}
if (pq->IsTonerLow)
{
statusReport = statusReport + "Is low on toner. ";
}
if (pq->NeedUserIntervention)
{
statusReport = statusReport + "Needs user intervention. ";
}
// Check if queue is even available at this time of day
// The following method is defined in the complete example.
ReportAvailabilityAtThisTime(statusReport, pq);
};
// Check for possible trouble states of a printer using its properties
internal static void SpotTroubleUsingProperties(ref String statusReport, PrintQueue pq)
{
if (pq.HasPaperProblem)
{
statusReport = statusReport + "Has a paper problem. ";
}
if (!(pq.HasToner))
{
statusReport = statusReport + "Is out of toner. ";
}
if (pq.IsDoorOpened)
{
statusReport = statusReport + "Has an open door. ";
}
if (pq.IsInError)
{
statusReport = statusReport + "Is in an error state. ";
}
if (pq.IsNotAvailable)
{
statusReport = statusReport + "Is not available. ";
}
if (pq.IsOffline)
{
statusReport = statusReport + "Is off line. ";
}
if (pq.IsOutOfMemory)
{
statusReport = statusReport + "Is out of memory. ";
}
if (pq.IsOutOfPaper)
{
statusReport = statusReport + "Is out of paper. ";
}
if (pq.IsOutputBinFull)
{
statusReport = statusReport + "Has a full output bin. ";
}
if (pq.IsPaperJammed)
{
statusReport = statusReport + "Has a paper jam. ";
}
if (pq.IsPaused)
{
statusReport = statusReport + "Is paused. ";
}
if (pq.IsTonerLow)
{
statusReport = statusReport + "Is low on toner. ";
}
if (pq.NeedUserIntervention)
{
statusReport = statusReport + "Needs user intervention. ";
}
// Check if queue is even available at this time of day
// The following method is defined in the complete example.
ReportAvailabilityAtThisTime(ref statusReport, pq);
}//end SpotTroubleUsingProperties
' Check for possible trouble states of a printer using its properties
Friend Shared Sub SpotTroubleUsingProperties(ByRef statusReport As String, ByVal pq As PrintQueue)
If pq.HasPaperProblem Then
statusReport = statusReport & "Has a paper problem. "
End If
If Not(pq.HasToner) Then
statusReport = statusReport & "Is out of toner. "
End If
If pq.IsDoorOpened Then
statusReport = statusReport & "Has an open door. "
End If
If pq.IsInError Then
statusReport = statusReport & "Is in an error state. "
End If
If pq.IsNotAvailable Then
statusReport = statusReport & "Is not available. "
End If
If pq.IsOffline Then
statusReport = statusReport & "Is off line. "
End If
If pq.IsOutOfMemory Then
statusReport = statusReport & "Is out of memory. "
End If
If pq.IsOutOfPaper Then
statusReport = statusReport & "Is out of paper. "
End If
If pq.IsOutputBinFull Then
statusReport = statusReport & "Has a full output bin. "
End If
If pq.IsPaperJammed Then
statusReport = statusReport & "Has a paper jam. "
End If
If pq.IsPaused Then
statusReport = statusReport & "Is paused. "
End If
If pq.IsTonerLow Then
statusReport = statusReport & "Is low on toner. "
End If
If pq.NeedUserIntervention Then
statusReport = statusReport & "Needs user intervention. "
End If
' Check if queue is even available at this time of day
' The following method is defined in the complete example.
ReportAvailabilityAtThisTime(statusReport, pq)
End Sub
创建 ReportAvailabilityAtThisTime 方法时,需要确定队列是否在当天的当前时间可用。
如果StartTimeOfDay和UntilTimeOfDay属性相等,此方法将不执行任何操作;因为在那种情况下,打印机随时可用。 如果它们不同,该方法将获取当前时间,然后必须转换为过去午夜的总分钟数,因为StartTimeOfDay属性UntilTimeOfDayInt32表示午夜后分钟,而不是DateTime对象。 最后,该方法检查当前时间是否在开始时间与“直到”时间之间。
private:
static void ReportAvailabilityAtThisTime (System::String^% statusReport, System::Printing::PrintQueue^ pq)
{
if (pq->StartTimeOfDay != pq->UntilTimeOfDay)
{
System::DateTime utcNow = DateTime::UtcNow;
System::Int32 utcNowAsMinutesAfterMidnight = (utcNow.TimeOfDay.Hours * 60) + utcNow.TimeOfDay.Minutes;
// If now is not within the range of available times . . .
if (!((pq->StartTimeOfDay < utcNowAsMinutesAfterMidnight) && (utcNowAsMinutesAfterMidnight < pq->UntilTimeOfDay)))
{
statusReport = statusReport + " Is not available at this time of day. ";
}
}
};
private static void ReportAvailabilityAtThisTime(ref String statusReport, PrintQueue pq)
{
if (pq.StartTimeOfDay != pq.UntilTimeOfDay) // If the printer is not available 24 hours a day
{
DateTime utcNow = DateTime.UtcNow;
Int32 utcNowAsMinutesAfterMidnight = (utcNow.TimeOfDay.Hours * 60) + utcNow.TimeOfDay.Minutes;
// If now is not within the range of available times . . .
if (!((pq.StartTimeOfDay < utcNowAsMinutesAfterMidnight)
&&
(utcNowAsMinutesAfterMidnight < pq.UntilTimeOfDay)))
{
statusReport = statusReport + " Is not available at this time of day. ";
}
}
}
Private Shared Sub ReportAvailabilityAtThisTime(ByRef statusReport As String, ByVal pq As PrintQueue)
If pq.StartTimeOfDay <> pq.UntilTimeOfDay Then ' If the printer is not available 24 hours a day
Dim utcNow As Date = Date.UtcNow
Dim utcNowAsMinutesAfterMidnight As Int32 = (utcNow.TimeOfDay.Hours * 60) + utcNow.TimeOfDay.Minutes
' If now is not within the range of available times . . .
If Not((pq.StartTimeOfDay < utcNowAsMinutesAfterMidnight) AndAlso (utcNowAsMinutesAfterMidnight < pq.UntilTimeOfDay)) Then
statusReport = statusReport & " Is not available at this time of day. "
End If
End If
End Sub