打印原始数据时缩放的文档

Question

我试图打印pdf文件直接在打印机上，这支持postscript。不幸的是，打印的文档是缩放的(比来自adobe阅读器的打印要小一些，具有缩放模式--“实际大小”)。有没有办法不用缩放就打印出来？下面是我用来打印的代码：

  [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Interoperability", "CA1401:PInvokesShouldNotBeVisible"), DllImport("winspool.Drv", EntryPoint = "OpenPrinterA", SetLastError = true, CharSet = CharSet.Ansi, ExactSpelling = true, CallingConvention = CallingConvention.StdCall, ThrowOnUnmappableChar = true, BestFitMapping = false)]
    public static extern bool OpenPrinter([MarshalAs(UnmanagedType.LPStr)] string szPrinter, out IntPtr hPrinter, IntPtr pd);

    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Interoperability", "CA1401:PInvokesShouldNotBeVisible"), DllImport("winspool.Drv", EntryPoint = "ClosePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
    public static extern bool ClosePrinter(IntPtr hPrinter);

    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Interoperability", "CA1401:PInvokesShouldNotBeVisible"), DllImport("winspool.Drv", EntryPoint = "StartDocPrinterA", SetLastError = true, CharSet = CharSet.Ansi, ExactSpelling = true, CallingConvention = CallingConvention.StdCall, ThrowOnUnmappableChar = true, BestFitMapping = false)]
    public static extern bool StartDocPrinter(IntPtr hPrinter, Int32 level, [In, MarshalAs(UnmanagedType.LPStruct)] DOCINFOA di);

    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Interoperability", "CA1401:PInvokesShouldNotBeVisible"), DllImport("winspool.Drv", EntryPoint = "EndDocPrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
    public static extern bool EndDocPrinter(IntPtr hPrinter);

    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Interoperability", "CA1401:PInvokesShouldNotBeVisible"), DllImport("winspool.Drv", EntryPoint = "StartPagePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
    public static extern bool StartPagePrinter(IntPtr hPrinter);

    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Interoperability", "CA1401:PInvokesShouldNotBeVisible"), DllImport("winspool.Drv", EntryPoint = "EndPagePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
    public static extern bool EndPagePrinter(IntPtr hPrinter);

    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Interoperability", "CA1401:PInvokesShouldNotBeVisible"), DllImport("winspool.Drv", EntryPoint = "WritePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
    public static extern bool WritePrinter(IntPtr hPrinter, IntPtr pBytes, Int32 dwCount, out Int32 dwWritten);


    public static bool SendFileToPrinter(string pdfFileName, string printerName, string name)
    {
        try
        {
            bool success = false;
            using (FileStream fs = new FileStream(pdfFileName, FileMode.Open))
            {
                int nLength = Convert.ToInt32(fs.Length);

                BinaryReader br = new BinaryReader(fs);

                Byte[] bytes = new Byte[fs.Length];
                bytes = br.ReadBytes(nLength);

                IntPtr ptrUnmanagedBytes = new IntPtr(0);
                ptrUnmanagedBytes = Marshal.AllocCoTaskMem(nLength);

                Marshal.Copy(bytes, 0, ptrUnmanagedBytes, nLength);

                success = SendBytesToPrinter(printerName, ptrUnmanagedBytes, nLength, name);

                Marshal.FreeCoTaskMem(ptrUnmanagedBytes);
            }
            return success;
        }
        catch (Exception ex)
        {
            throw new Exception(ex.Message);
        }
    }


    private static bool SendBytesToPrinter(string szPrinterName, IntPtr pBytes, Int32 dwCount, string name)
    {
        try
        {
            Int32 dwError = 0, dwWritten = 0;
            IntPtr hPrinter = new IntPtr(0);
            DOCINFOA di = new DOCINFOA();
            bool success = false; // Assume failure unless you specifically succeed.

            di.pDocName = name;
            di.pDataType = "RAW";

            if (OpenPrinter(szPrinterName.Normalize(), out hPrinter, IntPtr.Zero))
            {
                if (StartDocPrinter(hPrinter, 1, di))
                {
                    if (StartPagePrinter(hPrinter))
                    {
                        success = WritePrinter(hPrinter, pBytes, dwCount, out dwWritten);
                        EndPagePrinter(hPrinter);
                    }
                    EndDocPrinter(hPrinter);
                }
                ClosePrinter(hPrinter);
            }

            if (success == false)
            {
                dwError = Marshal.GetLastWin32Error();
            }
            return success;
        }
        catch (Exception ex)
        {
            throw new Exception(ex.Message);
        }
    }

顺便说一句，当我那样打印的时候，我能管理打印机的边距吗？

谢谢，巴托兹

Answer 1

谢谢你的建议@KenS，我终于找到了一个解决办法，为什么PDF没有正确打印。默认的PDF缩放有一个问题，这是为了使打印适合页面。解决这一问题的方法是设置缩放：

/ViewerPreferences<</PrintScaling/None>> 

例如，在PDF文件中：

对象之前：

2 0 obj
<<
/Type/Catalog
/Pages 3
>>
endobj

对象在以下之后：

2 0 obj
<<
/Type/Catalog
/ViewerPreferences<</PrintScaling/None>>
/Pages 3
>>
endobj

Answer 2

PDF和PostScript不是一回事！仅仅因为你的打印机‘支持PostScript’并不意味着它可以打印PDF文件。

在这种情况下，看起来您的打印机确实支持PDF打印。对于扩展输出有两个可能的原因：

1) PDF文件的媒体大小与打印机中的媒体不匹配。

( 2)打印机具有不可打印的边距。为了确保完整的PDF文件被打印出来(如果它包含直到媒体边缘的绘图操作)，打印机对PDF进行缩放，以便PDF媒体适合印刷媒体的可打印区域。

您可以对照打印机中的媒体检查PDF页的媒体大小。如果他们匹配的话，那你就知道不是这样的。

解决方案完全取决于打印机的功能。您可以告诉它不要缩放输出(如果您确信PDF的标记区域将适合打印页面的可打印区域)。如果没有，那么您的唯一解决方案是使用更小的媒体重新生成PDF文件。

您还可以尝试在PDF文件中设置一个比打印媒体更小的CropBox，并查看您的打印机是否会打印不缩放的PDF。