impressão Xps do serviço do Windows

9

Estou tentando imprimir documentos XPS de um serviço do Windows na estrutura .net. Como a Microsoft não oferece suporte à impressão usando System.Drawing.Printing nem usando System.Printing (WPF), estou usando a API XPSPrint nativa. Isto é sugerido para mim por Aspose em link .

Quando tento imprimir um documento XPS de um serviço do Windows, o resultado contém caracteres estranhos em vez do texto que desejo.

Eu tentei com impressoras diferentes (incluindo impressoras virtuais como por exemplo o PDFCreator), diferentes usuários e privilégios de usuário para o serviço, diferentes geradores xps (aspose, word 2007, word 2010), plataformas diferentes (windows 7, windows 2008 R2 ) mas todos têm o mesmo resultado.

Alguém sabe como resolver isso? Qualquer ajuda seria apreciada!

Para quem quiser experimentar, compartilhei alguns arquivos por meio de:

link

  • document.xps: o documento XPS para imprimir
  • document_printed_to_pdfcreator.pdf: o documento impresso que demonstra o que está errado
  • XpsPrintTest.zip: uma amostra da solução VS2010 com o código de amostra

O código de amostra para o serviço de janelas gerenciadas é:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Linq;
using System.ServiceProcess;
using System.Text;
using System.IO;
using System.Threading;
using System.Runtime.InteropServices;

namespace PrintXpsService
{
public partial class XpsPrintService : ServiceBase
{
    // Change name of printer here
    private String f_printerName = "PDFCreator";

    // path to some file where logging is done
    private String f_logFile = @"C:\temp\testdoc\xps_printing_service_log.txt";

    // path to xps file to print
    private String f_xpsFile = @"C:\temp\testdoc\document.xps";

    public XpsPrintService()
    {
        InitializeComponent();
    }

    private void Log(String fmt, params Object[] args)
    {
        try
        {
            DateTime now = DateTime.Now;

            using (StreamWriter wrt = new StreamWriter(f_logFile, true))
            {
                wrt.Write("{0} {1} - ", now.ToShortDateString(), now.ToShortTimeString());
                wrt.WriteLine(fmt, args);
            }
        }
        catch (Exception ex)
        {
        }
    }

    protected override void OnStart(string[] args)
    {
        // uncomment to allow to connect debugger
        //int i = 0;
        //while (i == 0)
        //{
        //    if (i == 0)
        //    {
        //        Thread.Sleep(1000);
        //    }
        //}

        Log("Starting Service");
        try
        {
            Log("Printing xps file {0}", f_xpsFile);

            using (Stream stream = new FileStream(f_xpsFile, FileMode.Open, FileAccess.Read))
            {
                Log("Starting to print on printer {0}", f_printerName);
                String jobName = f_xpsFile;
                this.Print(stream, jobName);
            }
            Log("Document printed");
        }
        catch (Exception ex)
        {
            Log("Exception during execution: {0}", ex.Message);
            Log("  {0}", ex.StackTrace);
            Exception inner = ex.InnerException;
            while (inner != null)
            {
                Log("=== Inner Exception: {0}", inner.Message);
                Log("    {0}", inner.StackTrace);
                inner = inner.InnerException;
            }
        }
    }

    protected override void OnStop()
    {
    }

    public void Print(Stream stream, String jobName)
    {
        String printerName = f_printerName;
        IntPtr completionEvent = CreateEvent(IntPtr.Zero, true, false, null);
        try
        {
            IXpsPrintJob job;
            IXpsPrintJobStream jobStream;

            StartJob(printerName, jobName, completionEvent, out job, out jobStream);
            CopyJob(stream, job, jobStream);
            WaitForJob(completionEvent, -1);
            CheckJobStatus(job);
        }
        finally
        {
            if (completionEvent != IntPtr.Zero)
                CloseHandle(completionEvent);
        }
    }

    private void StartJob(String printerName,
        String jobName, IntPtr completionEvent,
        out IXpsPrintJob job,
        out IXpsPrintJobStream jobStream)
    {
        int result = StartXpsPrintJob(printerName, jobName, null, IntPtr.Zero, completionEvent,
            null, 0, out job, out jobStream, IntPtr.Zero);
        if (result != 0)
            throw new Win32Exception(result);
    }


    private void CopyJob(Stream stream, IXpsPrintJob job, IXpsPrintJobStream jobStream)
    {
        try
        {
            byte[] buff = new byte[4096];
            while (true)
            {
                uint read = (uint)stream.Read(buff, 0, buff.Length);
                if (read == 0)
                    break;
                uint written;
                jobStream.Write(buff, read, out written);

                if (read != written)
                    throw new Exception("Failed to copy data to the print job stream.");
            }

            // Indicate that the entire document has been copied.
            jobStream.Close();
        }
        catch (Exception)
        {
            // Cancel the job if we had any trouble submitting it.
            job.Cancel();
            throw;
        }
    }

    private void WaitForJob(IntPtr completionEvent, int timeout)
    {
        if (timeout < 0)
            timeout = -1;

        switch (WaitForSingleObject(completionEvent, timeout))
        {
            case WAIT_RESULT.WAIT_OBJECT_0:
                // Expected result, do nothing.
                break;

            case WAIT_RESULT.WAIT_TIMEOUT:
                // timeout expired
                throw new Exception("Timeout expired");

            case WAIT_RESULT.WAIT_FAILED:
                throw new Exception("Wait for the job to complete failed");

            default:
                throw new Exception("Unexpected result when waiting for the print job.");
        }
    }

    private void CheckJobStatus(IXpsPrintJob job)
    {
        XPS_JOB_STATUS jobStatus;
        job.GetJobStatus(out jobStatus);
        switch (jobStatus.completion)
        {
            case XPS_JOB_COMPLETION.XPS_JOB_COMPLETED:
                // Expected result, do nothing.
                break;
            case XPS_JOB_COMPLETION.XPS_JOB_IN_PROGRESS:
                // expected, do nothing, can occur when printer is paused
                break;
            case XPS_JOB_COMPLETION.XPS_JOB_FAILED:
                throw new Win32Exception(jobStatus.jobStatus);
            default:
                throw new Exception("Unexpected print job status.");
        }
    }

    [DllImport("XpsPrint.dll", EntryPoint = "StartXpsPrintJob")]
    private static extern int StartXpsPrintJob(
        [MarshalAs(UnmanagedType.LPWStr)] String printerName,
        [MarshalAs(UnmanagedType.LPWStr)] String jobName,
        [MarshalAs(UnmanagedType.LPWStr)] String outputFileName,
        IntPtr progressEvent,   // HANDLE
        IntPtr completionEvent, // HANDLE
        [MarshalAs(UnmanagedType.LPArray)] byte[] printablePagesOn,
        UInt32 printablePagesOnCount,
        out IXpsPrintJob xpsPrintJob,
        out IXpsPrintJobStream documentStream,
        IntPtr printTicketStream);  // This is actually "out IXpsPrintJobStream", but we don't use it and just want to pass null, hence IntPtr.

    [DllImport("Kernel32.dll", SetLastError = true)]
    private static extern IntPtr CreateEvent(IntPtr lpEventAttributes, bool bManualReset, bool bInitialState, string lpName);

    [DllImport("Kernel32.dll", SetLastError = true, ExactSpelling = true)]
    private static extern WAIT_RESULT WaitForSingleObject(IntPtr handle, Int32 milliseconds);

    [DllImport("Kernel32.dll", SetLastError = true)]
    [return: MarshalAs(UnmanagedType.Bool)]
    private static extern bool CloseHandle(IntPtr hObject);
}

/// <summary>
/// This interface definition is HACKED.
/// 
/// It appears that the IID for IXpsPrintJobStream specified in XpsPrint.h as 
/// MIDL_INTERFACE("7a77dc5f-45d6-4dff-9307-d8cb846347ca") is not correct and the RCW cannot return it.
/// But the returned object returns the parent ISequentialStream inteface successfully.
/// 
/// So the hack is that we obtain the ISequentialStream interface but work with it as 
/// with the IXpsPrintJobStream interface. 
/// </summary>
[Guid("0C733A30-2A1C-11CE-ADE5-00AA0044773D")]  // This is IID of ISequenatialSteam.
[InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
interface IXpsPrintJobStream
{
    // ISequentualStream methods.
    void Read([MarshalAs(UnmanagedType.LPArray)] byte[] pv, uint cb, out uint pcbRead);
    void Write([MarshalAs(UnmanagedType.LPArray)] byte[] pv, uint cb, out uint pcbWritten);
    // IXpsPrintJobStream methods.
    void Close();
}

[Guid("5ab89b06-8194-425f-ab3b-d7a96e350161")]
[InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
interface IXpsPrintJob
{
    void Cancel();
    void GetJobStatus(out XPS_JOB_STATUS jobStatus);
}

[StructLayout(LayoutKind.Sequential)]
struct XPS_JOB_STATUS
{
    public UInt32 jobId;
    public Int32 currentDocument;
    public Int32 currentPage;
    public Int32 currentPageTotal;
    public XPS_JOB_COMPLETION completion;
    public Int32 jobStatus; // UInt32
};

enum XPS_JOB_COMPLETION
{
    XPS_JOB_IN_PROGRESS = 0,
    XPS_JOB_COMPLETED = 1,
    XPS_JOB_CANCELLED = 2,
    XPS_JOB_FAILED = 3
}

enum WAIT_RESULT
{
    WAIT_OBJECT_0 = 0,
    WAIT_ABANDONED = 0x80,
    WAIT_TIMEOUT = 0x102,
    WAIT_FAILED = -1 // 0xFFFFFFFF
}
}

Nota: alguns links para mais informações:

por Steven 25.05.2011 в 13:10
fonte

1 resposta

5

Falei com a microsoft sobre esse problema e descobrimos que o problema está relacionado à substituição incorreta de fontes no spooler da impressora. Quando a impressora está configurada para não colocar os documentos no spool, eles são impressos corretamente, também de um serviço do Windows. Caso contrário, todas as fontes, exceto arial (e talvez algumas outras), serão substituídas por outra fonte. Na amostra que forneci, o calibri é substituído por wingdings.

Então, eles reconhecem que isso é um bug, mas no momento eles não o resolverão. Dependerá de quantas pessoas sofrerão este bug para que decidam se não estão dispostas a corrigi-lo ...

    
por Steven 13.07.2011 / 14:31
fonte