How to Add Page number in Footer in PDF by Itextsh

问题:

I am using iTextSharp DLL in ASP.NET code. I am fetching a data into dataset and Add the dataset into PDF table.

If my dataset have more 100 rows then 100 rows will be added into PDF table and 3 or 4 page will be created in PDF file.

How can I add the footer in each page?

回答1:

You need to inherit from PdfPageEventHelper class and override the methods shown in the code snippet below:

Document doc = new Document(PageSize.A4.Rotate());        

using (MemoryStream ms = new MemoryStream())
{
  PdfWriter writer = PdfWriter.GetInstance(doc, ms);
  PageEventHelper pageEventHelper = new PageEventHelper();
  writer.PageEvent = pageEventHelper;
}

 public class PageEventHelper : PdfPageEventHelper
    {
        PdfContentByte cb;
        PdfTemplate template;


        public override void OnOpenDocument(PdfWriter writer, Document document)
        {
            cb = writer.DirectContent;
            template = cb.CreateTemplate(50, 50);
        }

        public override void OnEndPage(PdfWriter writer, Document document)
        {
            base.OnEndPage(writer, document);

            int pageN = writer.PageNumber;
            String text = "Page " + pageN.ToString() + " of ";
            float len = this.RunDateFont.BaseFont.GetWidthPoint(text, this.RunDateFont.Size);

            iTextSharp.text.Rectangle pageSize = document.PageSize;

            cb.SetRGBColorFill(100, 100, 100);

            cb.BeginText();
            cb.SetFontAndSize(this.RunDateFont.BaseFont, this.RunDateFont.Size);
            cb.SetTextMatrix(document.LeftMargin, pageSize.GetBottom(document.BottomMargin));
            cb.ShowText(text);

            cb.EndText();

            cb.AddTemplate(template, document.LeftMargin + len, pageSize.GetBottom(document.BottomMargin));
        }

        public override void OnCloseDocument(PdfWriter writer, Document document)
        {
            base.OnCloseDocument(writer, document);

            template.BeginText();
            template.SetFontAndSize(this.RunDateFont.BaseFont, this.RunDateFont.Size);
            template.SetTextMatrix(0, 0);
            template.ShowText("" + (writer.PageNumber - 1));
            template.EndText();
        }
    }

回答2:

Here is another approach, make templates on each page and then at onCloseDocument update those templates look at the code below I am using iTextSharp 7

 class PDFBackgroundHelper : PdfPageEventHelper
{

    private PdfContentByte cb;
    private List<PdfTemplate> templates;
    //constructor
    public PDFBackgroundHelper()
    {
        this.templates = new List<PdfTemplate>();
    }

    public override void OnEndPage(PdfWriter writer, Document document)
    {
        base.OnEndPage(writer, document);

        cb = writer.DirectContentUnder;
        PdfTemplate templateM = cb.CreateTemplate(50, 50);
        templates.Add(templateM);

        int pageN = writer.CurrentPageNumber;
        String pageText = "Page " + pageN.ToString() +" of ";
        BaseFont bf = BaseFont.CreateFont(BaseFont.HELVETICA, BaseFont.CP1252, BaseFont.NOT_EMBEDDED);
        float len = bf.GetWidthPoint(pageText, 10);
        cb.BeginText();
        cb.SetFontAndSize(bf, 10);
        cb.SetTextMatrix(document.LeftMargin, document.PageSize.GetBottom(document.BottomMargin));
        cb.ShowText(pageText);
        cb.EndText();
        cb.AddTemplate(templateM, document.LeftMargin + len, document.PageSize.GetBottom(document.BottomMargin));
    }

    public override void OnCloseDocument(PdfWriter writer, Document document)
    {
        base.OnCloseDocument(writer, document);
        BaseFont bf = BaseFont.CreateFont(BaseFont.HELVETICA, BaseFont.CP1252, BaseFont.NOT_EMBEDDED);
        foreach (PdfTemplate item in templates)
        {
            item.BeginText();
            item.SetFontAndSize(bf, 10);
            item.SetTextMatrix(0, 0);
            item.ShowText("" + (writer.PageNumber));
            item.EndText();
        }

    } 

回答3:

You must inherit pageeventhepler to add page number to dynamically generated pdf pages.

public void printPdf()
{
    Document doc = new Document(PageSize.A4.Rotate());
    using (MemoryStream ms = new MemoryStream())
    {
        PdfWriter writer = PdfWriter.GetInstance(doc, ms);
        PageEventHelper pageEventHelper = new PageEventHelper();
        writer.PageEvent = pageEventHelper;
    }
}

public class PageEventHelper : PdfPageEventHelper
{
    PdfContentByte cb;
    PdfTemplate template;


    public override void OnOpenDocument(PdfWriter writer, Document document)
    {
        cb = writer.DirectContent;
        template = cb.CreateTemplate(50, 50);
    }

    public override void OnEndPage(PdfWriter writer, Document document)
    {
        base.OnEndPage(writer, document);

        int pageN = writer.PageNumber;
        String text = "Page " + pageN.ToString() + " of ";
        float len = this.RunDateFont.BaseFont.GetWidthPoint(text, this.RunDateFont.Size);

        iTextSharp.text.Rectangle pageSize = document.PageSize;

        cb.SetRGBColorFill(100, 100, 100);

        cb.BeginText();
        cb.SetFontAndSize(this.RunDateFont.BaseFont, this.RunDateFont.Size);
        cb.SetTextMatrix(document.LeftMargin, pageSize.GetBottom(document.BottomMargin));
        cb.ShowText(text);

        cb.EndText();

        cb.AddTemplate(template, document.LeftMargin + len, pageSize.GetBottom(document.BottomMargin));
    }

    public override void OnCloseDocument(PdfWriter writer, Document document)
    {
        base.OnCloseDocument(writer, document);

        template.BeginText();
        template.SetFontAndSize(this.RunDateFont.BaseFont, this.RunDateFont.Size);
        template.SetTextMatrix(0, 0);
        template.ShowText("" + (writer.PageNumber - 1));
        template.EndText();
    }
}