如何列印 XPS 檔案 (WPF .NET)

有時您會想要將新的列印工作新增至列印佇列，而不要開啟列印對話方塊。 您可以使用其中一種 PrintQueue.AddJob 方法來這麼做。 方法如下。

在下列範例中，我們使用 AddJob(String, String, Boolean) 方法 (AddJob 的數種多載之一) 來執行下列作業：

• 將 XML 文件規格 (XPS) 文件的新列印工作新增至預設的列印佇列。
• 命名新工作。
• 指定是否應該驗證 XPS 文件 (使用 fastCopy 參數)。

使用 AddJob(String, String, Boolean) 方法時，fastCopy 參數的值是一個重要考慮因素：

• 如果您將 fastCopy 參數設定為 true，則會略過 XPS 驗證，而且列印作業會快速多工緩衝處理，而不會產生逐頁處理進度意見反應。
• 如果您將 fastCopy 參數設定為 false，則呼叫 AddJob 方法的執行緒必須具有單一執行緒 Apartment 狀態，否則將會擲回例外狀況。 如需詳細資訊，請參閱備註一節中的 AddJob(String, String, Boolean)。

將新的列印工作新增至佇列

此範例會將一或多個 XPS 文件新增至預設佇列。 程式碼會：

1. 使用 Task.Run 來避免封鎖 UI 執行緒，因為沒有非同步版本的 AddJob。
2. 如果 fastCopy 參數值為 false，請在具有AddJob(String, String, Boolean)的執行緒上執行 。
3. 取得 PrintQueue 的預設 LocalPrintServer 的參考。
4. 在列印佇列參考上呼叫 AddJob(String, String, Boolean)、傳入工作名稱、XPS 文件路徑和 fastCopy 參數。

如果佇列未暫停且印表機正在運作，則列印工作會在到達列印佇列頂端時自動開始列印。

/// <summary>
/// Asyncronously, add a batch of XPS documents to the print queue using a PrintQueue.AddJob method.
/// Handle the thread apartment state required by the PrintQueue.AddJob method.
/// </summary>
/// <param name="xpsFilePaths">A collection of XPS documents.</param>
/// <param name="fastCopy">Whether to validate the XPS documents.</param>
/// <returns>Whether all documents were added to the print queue.</returns>
public static async Task<bool> BatchAddToPrintQueueAsync(IEnumerable<string> xpsFilePaths, bool fastCopy = false)
{
    bool allAdded = true;

    // Queue some work to run on the ThreadPool.
    // Wait for completion without blocking the calling thread.
    await Task.Run(() =>
    {
        if (fastCopy)
            allAdded = BatchAddToPrintQueue(xpsFilePaths, fastCopy);
        else
        {
            // Create a thread to call the PrintQueue.AddJob method.
            Thread newThread = new(() =>
            {
                allAdded = BatchAddToPrintQueue(xpsFilePaths, fastCopy);
            });

            // Set the thread to single-threaded apartment state.
            newThread.SetApartmentState(ApartmentState.STA);

            // Start the thread.
            newThread.Start();

            // Wait for thread completion. Blocks the calling thread,
            // which is a ThreadPool thread.
            newThread.Join();
        }
    });

    return allAdded;
}

/// <summary>
/// Add a batch of XPS documents to the print queue using a PrintQueue.AddJob method.
/// </summary>
/// <param name="xpsFilePaths">A collection of XPS documents.</param>
/// <param name="fastCopy">Whether to validate the XPS documents.</param>
/// <returns>Whether all documents were added to the print queue.</returns>
public static bool BatchAddToPrintQueue(IEnumerable<string> xpsFilePaths, bool fastCopy)
{
    bool allAdded = true;

    // To print without getting the "Save Output File As" dialog, ensure
    // that your default printer is not the Microsoft XPS Document Writer,
    // Microsoft Print to PDF, or other print-to-file option.

    // Get a reference to the default print queue.
    PrintQueue defaultPrintQueue = LocalPrintServer.GetDefaultPrintQueue();

    // Iterate through the document collection.
    foreach (string xpsFilePath in xpsFilePaths)
    {
        // Get document name.
        string xpsFileName = Path.GetFileName(xpsFilePath);

        try
        {
            // The AddJob method adds a new print job for an XPS
            // document into the print queue, and assigns a job name.
            // Use fastCopy to skip XPS validation and progress notifications.
            // If fastCopy is false, the thread that calls PrintQueue.AddJob
            // must have a single-threaded apartment state.
            PrintSystemJobInfo xpsPrintJob =
                    defaultPrintQueue.AddJob(jobName: xpsFileName, documentPath: xpsFilePath, fastCopy);

            // If the queue is not paused and the printer is working, then jobs will automatically begin printing.
            Debug.WriteLine($"Added {xpsFileName} to the print queue.");
        }
        catch (PrintJobException e)
        {
            allAdded = false;
            Debug.WriteLine($"Failed to add {xpsFileName} to the print queue: {e.Message}\r\n{e.InnerException}");
        }
    }

    return allAdded;
}

''' <summary>
''' Asyncronously, add a batch of XPS documents to the print queue using a PrintQueue.AddJob method.
''' Handle the thread apartment state required by the PrintQueue.AddJob method.
''' </summary>
''' <param name="xpsFilePaths">A collection of XPS documents.</param>
''' <param name="fastCopy">Whether to validate the XPS documents.</param>
''' <returns>Whether all documents were added to the print queue.</returns>
Public Shared Async Function BatchAddToPrintQueueAsync(xpsFilePaths As IEnumerable(Of String), Optional fastCopy As Boolean = False) As Task(Of Boolean)

    Dim isAllPrinted As Boolean = True

    ' Queue some work to run on the ThreadPool.
    ' Wait for completion without blocking the calling thread.
    Await Task.Run(
        Sub()
            If fastCopy Then
                isAllPrinted = BatchAddToPrintQueue(xpsFilePaths, fastCopy)
            Else
                ' Create a thread to call the PrintQueue.AddJob method.
                Dim newThread As New Thread(
                    Sub()
                        isAllPrinted = BatchAddToPrintQueue(xpsFilePaths, fastCopy)
                    End Sub
                )

                ' Set the thread to single-threaded apartment state.
                newThread.SetApartmentState(ApartmentState.STA)

                ' Start the thread.
                newThread.Start()

                ' Wait for thread completion. Blocks the calling thread,
                ' which is a ThreadPool thread.
                newThread.Join()
            End If
        End Sub
    )

    Return isAllPrinted

End Function

''' <summary>
''' Add a batch of XPS documents to the print queue using a PrintQueue.AddJob method.
''' </summary>
''' <param name="xpsFilePaths">A collection of XPS documents.</param>
''' <param name="fastCopy">Whether to validate the XPS documents.</param>
''' <returns>Whether all documents were added to the print queue.</returns>
Public Shared Function BatchAddToPrintQueue(xpsFilePaths As IEnumerable(Of String), fastCopy As Boolean) As Boolean

    Dim isAllPrinted As Boolean = True

    ' To print without getting the "Save Output File As" dialog, ensure
    ' that your default printer is not the Microsoft XPS Document Writer,
    ' Microsoft Print to PDF, or other print-to-file option.

    ' Get a reference to the default print queue.
    Dim defaultPrintQueue As PrintQueue = LocalPrintServer.GetDefaultPrintQueue()

    ' Iterate through the document collection.
    For Each xpsFilePath As String In xpsFilePaths

        ' Get document name.
        Dim xpsFileName As String = Path.GetFileName(xpsFilePath)

        Try
            ' The AddJob method adds a new print job for an XPS
            ' document into the print queue, and assigns a job name.
            ' Use fastCopy to skip XPS validation and progress notifications.
            ' If fastCopy is false, the thread that calls PrintQueue.AddJob
            ' must have a single-threaded apartment state.
            Dim xpsPrintJob As PrintSystemJobInfo = defaultPrintQueue.AddJob(jobName:=xpsFileName, documentPath:=xpsFilePath, fastCopy)

            ' If the queue is not paused and the printer is working, then jobs will automatically begin printing.
            Debug.WriteLine($"Added {xpsFileName} to the print queue.")
        Catch e As PrintJobException
            isAllPrinted = False
            Debug.WriteLine($"Failed to add {xpsFileName} to the print queue: {e.Message}\r\n{e.InnerException}")
        End Try
    Next

    Return isAllPrinted

End Function

另請參閱

• PrintQueue.AddJob
• WPF 中的文件
• 如何顯示列印對話框
• 列印文件概觀