如何使用iText在每个页面上添加总页码?

2022-09-01 11:01:59

如何使用iText添加每个页面上的总页码?


答案 1
  1. 使用虚拟页数处理从 a 到第一个的输出。PdfWriterbytestream
  2. 从 中创建一个 ,调用以获取实际的页数。PdfReaderbytestreamPdfReader.getNumberOfPages
  3. 重新创建 PDF 输出,了解页数,并相应地更改页脚。

这很混乱,但是如果没有两次通过的方法,就没有简单的方法来了解页数。有关操作 PDF 的详细信息,请参阅示例代码


答案 2

您可以创建一个从中继承的类,然后重写这两个函数,如下所示:PdfPageEventHelper

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,只需像这样设置您的值:pdfwriter PageEvent

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

推荐