如何在带有IText的每页上添加总页数?

1. 处理来自 PdfWriter 到A bytestream 首先是一个伪页计数。
2. 创建一个 PdfReader 从那 旁通流 呼唤 PdfReader.getNumberOfPages 以获取实际的页面计数。
3. 重新创建PDF输出,知道页数是多少,相应地更改页脚。

这很混乱,但是如果没有两次通过的方法,就很难知道页数。见 example code 有关操作PDF的详细信息。

可以创建继承自的类 PdfPageEventHelper 然后覆盖这两个功能:

Imports System.Collections.Generic
Imports System.Text

Imports iTextSharp.text.pdf
Imports iTextSharp.text

Namespace PDF_EnteteEtPiedDePage
    Public Class EnteteEtPiedDePage
        Inherits PdfPageEventHelper
        ' This is the contentbyte object of the writer
        Private cb As PdfContentByte

        ' we will put the final number of pages in a template
        Private template As PdfTemplate

        ' this is the BaseFont we are going to use for the header / footer
        Private bf As BaseFont = Nothing

        ' This keeps track of the creation time
        Private PrintTime As DateTime = DateTime.Now

        ' we override the onOpenDocument method
        Public Overrides Sub OnOpenDocument(writer As PdfWriter, document As Document)
            Try
                PrintTime = DateTime.Now
                bf = BaseFont.CreateFont(BaseFont.HELVETICA, BaseFont.CP1252, BaseFont.NOT_EMBEDDED)
                cb = writer.DirectContent
                template = cb.CreateTemplate(50, 50)
            Catch de As DocumentException
            Catch ioe As System.IO.IOException
            End Try
        End Sub

        Public Overrides Sub OnStartPage(writer As PdfWriter, document As Document)
            MyBase.OnStartPage(writer, document)

            Dim pageSize As Rectangle = document.PageSize

        End Sub

        Public Overrides Sub OnEndPage(writer As PdfWriter, document As Document)
            MyBase.OnEndPage(writer, document)

            Dim pageN As Integer = writer.PageNumber
            Dim text As [String] = "Page " & pageN & " de "
            Dim len As Single = bf.GetWidthPoint(text, 8)

            Dim pageSize As Rectangle = document.PageSize

            cb.SetRGBColorFill(100, 100, 100)

            cb.BeginText()
            cb.SetFontAndSize(bf, 8)
            cb.SetTextMatrix(pageSize.GetLeft(40), pageSize.GetBottom(30))
            cb.ShowText(text)
            cb.EndText()

            cb.AddTemplate(template, pageSize.GetLeft(40) + len, pageSize.GetBottom(30))

            cb.BeginText()
            cb.SetFontAndSize(bf, 8)
            cb.ShowTextAligned(PdfContentByte.ALIGN_RIGHT, "Imprimé le : " & PrintTime.ToShortDateString() & " à " & PrintTime.ToShortTimeString, pageSize.GetRight(40), pageSize.GetBottom(30), 0)
            cb.EndText()
        End Sub

        Public Overrides Sub OnCloseDocument(writer As PdfWriter, document As Document)
            MyBase.OnCloseDocument(writer, document)

            template.BeginText()
            template.SetFontAndSize(bf, 8)
            template.SetTextMatrix(0, 0)
            template.ShowText("" & Convert.ToString((writer.PageNumber - 1)))
            template.EndText()
        End Sub

    End Class
End Namespace

然后在那之后,只需设置 pdfwriter PageEvent 这样地:

Dim PageEventHandler = New EnteteEtPiedDePage()
            aPdfWriter.PageEvent = PageEventHandler

不再搜索,这里是解决方案。如果他们删除了这个链接,我将把代码发布到我的站点并托管这个链接。

iText page numbers example

这是我使用的代码。将页面写入输出不会增加太多开销。

outputStream = new ByteArrayOutputStream();
output = new DataOutputStream(outputStream);
document = new Document();
writer = PdfWriter.getInstance(document, output);
document.open();
contentByte = writer.getDirectContent();
....add stuff
document.close();
writer.close();
byte[] output = outputStream.toByteArray();
PdfReader reader = new PdfReader(output);
//reset the output
outputStream = new ByteArrayOutputStream();
output = new DataOutputStream(outputStream);
document = new Document();
writer = PdfWriter.getInstance(document, output);
document.open();
PdfStamper stamper = new PdfStamper(reader, outputStream);
//add the pages
for (int i = 1; i <= pageCount; i++)
{
    contentByte = stamper.getOverContent(i);
    addParagraph("Page " + i + " of " + pageCount, new Point(500, 30), boldTextFont);  // my own paragraph font
}
stamper.close();

从一个快速的网络搜索中提醒自己;看一下

Example

相关方法是 onEndPage() 生成“X”和 onCloseDocument() 当您到达文档结尾时生成“Y”。

这是一个方便的功能!(基于Milhous的方法)(使用IText版本4.1.6.0)

public static byte[] AddPageNumbers(byte[] pdf)
        {
            PdfReader reader = new PdfReader(pdf);
            var Pages = reader.NumberOfPages;
            MemoryStream ms = new MemoryStream();

            PdfStamper stamper = new PdfStamper(reader, ms);
            for (int i = 1; i <= Pages; i++)
            {
                PdfContentByte overContent;
                Font Signature = FontFactory.GetFont("Calibiri", 9, iTextSharp.text.Font.NORMAL, Color.BLACK);
                overContent = stamper.GetOverContent(i);
                var helv = BaseFont.CreateFont(BaseFont.HELVETICA, BaseFont.WINANSI, BaseFont.NOT_EMBEDDED);
                overContent.SaveState();
                overContent.BeginText();
                overContent.SetFontAndSize(helv, 10.0f);
                overContent.SetTextMatrix(PageSize.LETTER.Width / 2 - 20, PageSize.LETTER.Height - (PageSize.LETTER.Height - 20));
                overContent.ShowText("Page " + (i) + " of " + Pages);
                overContent.EndText();
                overContent.RestoreState();
            }
            stamper.Close();            
            return ms.ToArray();
        }

尝试这个,因为我也遭受了这个痛苦,我也新建了这个库,所以在很多麻烦之后,我得到的结果只是尝试应用逻辑两次,正如我在评论中提到的。

class PdfReportServlet extends HttpServlet
{
    public static int total = 0;

    public static int getTotal() 
    {
        return total;
    }

    public static void setTotal(int total) {
        PdfReportServlet .total = total;
    }


    public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException 
    {
        String reportFor = request.getParameter("report");
        if(!"".equals(reportFor))
        {
            if(reportFor.equals("pdf"))
            {
    /* 
       from here logic starts
    */
                response.setContentType("application/pdf");
                Document document = new Document(PageSize.LETTER.rotate());
                try
                {
                    ByteArrayOutputStream bos = new ByteArrayOutputStream();
                    PdfWriter pdfWriter = PdfWriter.getInstance(document, bos);
                    PdfReport pdfReport = new PdfReport();
                    pdfWriter.setPageEvent(pdfReport);
                    document.open();
                    String id = request.getParameter("id");
                    DettagliFamigliaPDFReport.generatePDFReport(document,id);
                    document.close();

                    /*
                     * now again give new references to Document and PdfWriter classes.
                     */

                    document = new Document(PageSize.LETTER.rotate());

                    pdfWriter = PdfWriter.getInstance(document, response.getOutputStream());
                    PDFReport.setTotalPages(getTotal());/*##PAGES_TOTAL here i set total Pages which i get from above logic */
                    PdfReport pdfReport = new PdfReport();
                    pdfWriter.setPageEvent(pdfReport);
                    document.open();
                    id = request.getParameter("id");
                    PDFReport.generatePDFReport(document,id);
                    document.close();

                }
                catch(DocumentException de){
                    de.printStackTrace();
                }
                catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }
    }


}


/*
    Here below i write the class inherits the PdfPageEventHelper class and also having generatePDFReport() method.
*/


public class PDFReport extends PdfPageEventHelper
{
    public static PdfTemplate template;
    public static int totalPages=0;

    public static int getTotalPages() {
        return totalPages;
    }

    public static void setTotalPages(int totalPages) {
        DettagliFamigliaPDFReport.totalPages = totalPages;
    }


    public static void generatePDFReport(Document document,String id)
    {
        // here your data to write on page of pdf.
    }

    @Override
    public void onOpenDocument(PdfWriter writer, Document doc) 
    {
        template = writer.getDirectContent().createTemplate(100, 100);
    }

    int totalPage = 0;
    @Override
    public void onCloseDocument(PdfWriter writer, Document doc) 
    {
        totalPage = writer.getPageNumber() - 1;/* at the end this method calls and you will get total number of pages.*/
        PdfReportServlet.setTotal(totalPage); /* while first time logic of servlet executes then i set the total pages to servlet's variable using this logic.
and second time servlet's logic is executing i passed totalPages to this class variable
where i marked ##PAGES_TOTAL  */
    }

    @Override
    public void onStartPage(PdfWriter writer, Document doc) {
        // Here i write header logic when each time page starts.
    }

    @Override`enter code here`
    public void onEndPage(PdfWriter writer, Document doc) 
    {
        Rectangle rect = writer.getPageSize();
        float width = rect.getWidth()/2;   

        DateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy");
        Date date = new Date();

        String footerOne = "This document is printed on date "+dateFormat.format(date)+" - Page. "+writer.getPageNumber()+" of "+getTotalPages();

        Paragraph paraOne = new Paragraph(footerOne);

        Font fontFooter = new Font();
        fontFooter.setSize(8);
        fontFooter.setColor(Color.gray);

        paraOne.setFont(fontFooter);

        Phrase footerPhraseOne = new Phrase(paraOne);
        ColumnText.showTextAligned(writer.getDirectContent(),
                Element.ALIGN_CENTER, footerPhraseOne,
                width, 30, 0);
    }
}

这是您的代码片段:

final PdfWriter writer = PdfWriter.getInstance(document, outputStream);
writer.setPageEvent(new PageStamper());

编号代码:

import com.itextpdf.text.*;
import com.itextpdf.text.pdf.*;
import com.itextpdf.tool.xml.*;
import com.itextpdf.tool.xml.css.*;

import java.io.IOException;

/**
 * Adds page number to al the pages except the first.
 */
public class PageStamper extends PdfPageEventHelper {
    private static final Logger logger = Logger.getLogger(PageStamper.class);

    @Override
    public void onEndPage(PdfWriter writer, Document document) {
        final int currentPageNumber = writer.getCurrentPageNumber();

        if (currentPageNumber == 1) {
            return;
        }

        try {
            final Rectangle pageSize = document.getPageSize();
            final PdfContentByte directContent = writer.getDirectContent();

            directContent.setColorFill(BaseColor.GRAY);
            directContent.setFontAndSize(BaseFont.createFont(), 10);

            directContent.setTextMatrix(pageSize.getRight(40), pageSize.getBottom(30));
            directContent.showText(String.valueOf(currentPageNumber));

        } catch (DocumentException | IOException e) {
            logger.error("PDF generation error", e);
        }
    }
}

此代码在此处找到: http://blog.abelsky.com/2014/01/22/adding-page-number-to-itext-generated-pdf/ . 非常感谢,722

如其他答案所示,您首先需要创建PDF,然后查看您创建的PDF包含的页面数,然后将页脚添加到每个页面。 理想的处理方法是pdfstamper,它的目的是向现有的pdf/existing pdf页面添加额外的元素。

下面是一个基于milhous示例的详细示例:

Font smallFont = FontFactory.getFont("Arial", 9, Font.NORMAL);
ByteArrayOutputStream pdfOutputStream = new ByteArrayOutputStream();
Document document = new Document(PageSize.A4, 70, 70, 40, 40);
PdfWriter pdfWriter = PdfWriter.getInstance(document, pdfOutputStream);

document.open();
//CREATE PDF HERE - ADD CONTENT TO DOCUMENT
document.close();

int pageCount = pdfWriter.getPageNumber()-1;
byte[] pdfAsBytes = pdfOutputStream.toByteArray();

//add footer
PdfReader reader = new PdfReader(pdfAsBytes);
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
DataOutputStream output = new DataOutputStream(outputStream);
document = new Document();
document.open();
PdfStamper stamper = new PdfStamper(reader, output);
for (int i = 1; i <= pageCount; i++) {
  ColumnText.showTextAligned(stamper.getOverContent(i), 
    Element.ALIGN_CENTER, new Phrase(i+"/" + pageCount, smallFont), 550, 30, 0);
}
stamper.close();
byte[] finalPdfAsBytes = outputStream.toByteArray();

这是在Java中转换的RAMA代码(至少部分)

public class test extends PdfPageEventHelper{
    private int _pg = 0;
    private BaseFont font;

    @Override
    public void onEndPage(PdfWriter writer, Document document) {
        _pg++;
        PdfContentByte cb = writer.getDirectContent();
        cb.beginText();
        try {
            Rectangle pageSize = document.getPageSize();
            cb.setFontAndSize(font, 8);
            cb.setTextMatrix(pageSize.getLeft(40), pageSize.getBottom(15));
            String s = "Page " + _pg + "/";
            cb.showText(s);
            cb.addTemplate(template, pageSize.getLeft(40) + font.getWidthPoint(s, 8), pageSize.getBottom(15));
        } catch (Exception exc) {
            logger.warn("got Exception : " + exc.getMessage());
        }
        cb.endText();
    }

    @Override
    public void onOpenDocument(PdfWriter writer, Document document) {
        super.onOpenDocument(writer, document);
        template = writer.getDirectContent().createTemplate(50, 50);
        try {
            font = BaseFont.createFont(BaseFont.COURIER, BaseFont.WINANSI, BaseFont.NOT_EMBEDDED);
        } catch (Exception exc) {
            logger.warn("got Exception : " + exc.getMessage());
        }
    }

    @Override
    public void onCloseDocument(PdfWriter writer, Document document) {
        super.onCloseDocument(writer, document);

        template.beginText();
        try {
            template.setFontAndSize(font, 8);
            template.setTextMatrix(0f, 0f);
            template.showText("" + (writer.getPageNumber() - 1));
        } catch (Exception ex) {
            logger.error(ex);
        }
        template.endText();
    }

}