这是我从一个旧项目中提取的一些代码。这是一个网络应用程序，但我使用 iTextSharp 合并 pdf 文件然后打印它们。
public static class PdfMerger
{
/// <summary>
/// Merge pdf files.
/// </summary>
/// <param name="sourceFiles">PDF files being merged.</param>
/// <returns></returns>
public static byte[] MergeFiles(List<Stream> sourceFiles)
{
Document document = new Document();
MemoryStream output = new MemoryStream();
try
{
// Initialize pdf writer
PdfWriter writer = PdfWriter.GetInstance(document, output);
writer.PageEvent = new PdfPageEvents();
// Open document to write
document.Open();
PdfContentByte content = writer.DirectContent;
// Iterate through all pdf documents
for (int fileCounter = 0; fileCounter < sourceFiles.Count; fileCounter++)
{
// Create pdf reader
PdfReader reader = new PdfReader(sourceFiles[fileCounter]);
int numberOfPages = reader.NumberOfPages;
// Iterate through all pages
for (int currentPageIndex = 1; currentPageIndex <=
numberOfPages; currentPageIndex++)
{
// Determine page size for the current page
document.SetPageSize(
reader.GetPageSizeWithRotation(currentPageIndex));
// Create page
document.NewPage();
PdfImportedPage importedPage =
writer.GetImportedPage(reader, currentPageIndex);
// Determine page orientation
int pageOrientation = reader.GetPageRotation(currentPageIndex);
if ((pageOrientation == 90) || (pageOrientation == 270))
{
content.AddTemplate(importedPage, 0, -1f, 1f, 0, 0,
reader.GetPageSizeWithRotation(currentPageIndex).Height);
}
else
{
content.AddTemplate(importedPage, 1f, 0, 0, 1f, 0, 0);
}
}
}
}
catch (Exception exception)
{
throw new Exception("There has an unexpected exception" +
" occured during the pdf merging process.", exception);
}
finally
{
document.Close();
}
return output.GetBuffer();
}
}
/// <summary>
/// Implements custom page events.
/// </summary>
internal class PdfPageEvents : IPdfPageEvent
{
#region members
private BaseFont _baseFont = null;
private PdfContentByte _content;
#endregion
#region IPdfPageEvent Members
public void OnOpenDocument(PdfWriter writer, Document document)
{
_baseFont = BaseFont.CreateFont(BaseFont.HELVETICA,
BaseFont.CP1252, BaseFont.NOT_EMBEDDED);
_content = writer.DirectContent;
}
public void OnStartPage(PdfWriter writer, Document document)
{ }
public void OnEndPage(PdfWriter writer, Document document)
{ }
public void OnCloseDocument(PdfWriter writer, Document document)
{ }
public void OnParagraph(PdfWriter writer,
Document document, float paragraphPosition)
{ }
public void OnParagraphEnd(PdfWriter writer,
Document document, float paragraphPosition)
{ }
public void OnChapter(PdfWriter writer, Document document,
float paragraphPosition, Paragraph title)
{ }
public void OnChapterEnd(PdfWriter writer,
Document document, float paragraphPosition)
{ }
public void OnSection(PdfWriter writer, Document document,
float paragraphPosition, int depth, Paragraph title)
{ }
public void OnSectionEnd(PdfWriter writer,
Document document, float paragraphPosition)
{ }
public void OnGenericTag(PdfWriter writer, Document document,
Rectangle rect, string text)
{ }
#endregion
private float GetCenterTextPosition(string text, PdfWriter writer)
{
return writer.PageSize.Width / 2 - _baseFont.GetWidthPoint(text, 8) / 2;
}
}
这不是我写的，而是做了一些修改。我不记得我在哪里找到的。合并 PDF 后，我会调用此方法插入 javascript，以便在打开 PDF 时打开打印对话框。如果您将 bSilent 更改为 true，那么它应该以静默方式打印到其默认打印机。
public Stream addPrintJStoPDF(Stream thePDF)
{
MemoryStream outPutStream = null;
PRStream finalStream = null;
PdfDictionary page = null;
string content = null;
//Open the stream with iTextSharp
var reader = new PdfReader(thePDF);
outPutStream = new MemoryStream(finalStream.GetBytes());
var stamper = new PdfStamper(reader, (MemoryStream)outPutStream);
var jsText = "var res = app.setTimeOut('this.print({bUI: true, bSilent: false, bShrinkToFit: false});', 200);";
//Add the javascript to the PDF
stamper.JavaScript = jsText;
stamper.FormFlattening = true;
stamper.Writer.CloseStream = false;
stamper.Close();
//Set the stream to the beginning
outPutStream.Position = 0;
return outPutStream;
}
不确定上面的代码写得有多好，因为我是从其他地方提取的，而且我根本没有深入使用 iTextSharp，但我知道它确实可以合并我在运行时生成的 PDF。