使用iTextsharp为PDF添加页眉和页脚

Question

如何在pdf中为每个页面添加页眉和页脚.

Headed将只包含一个文本页脚将包含pdf的文本和分页(页:1/4)

这怎么可能 ？我尝试添加以下行,但标题不会显示在pdf中.

document.AddHeader("Header", "Header Text");

这是我用于生成PDF的代码:

   protected void GeneratePDF_Click(object sender, EventArgs e)
    {
        DataTable dt = getData(); 

            Response.ContentType = "application/pdf";
            Response.AddHeader("content-disposition", "attachment;filename=Locations.pdf");
            Response.Cache.SetCacheability(HttpCacheability.NoCache);

            Document document = new Document();

            PdfWriter.GetInstance(document, Response.OutputStream);

            document.Open();

            iTextSharp.text.Font font5 = iTextSharp.text.FontFactory.GetFont(FontFactory.COURIER , 8);

            PdfPTable table = new PdfPTable(dt.Columns.Count);
            PdfPRow row = null;
            float[] widths = new float[] { 6f, 6f, 2f, 4f, 2f };

            table.SetWidths(widths);

            table.WidthPercentage = 100;
            int iCol = 0;
            string colname = "";
            PdfPCell cell = new PdfPCell(new Phrase("Locations"));

            cell.Colspan = dt.Columns.Count;

            foreach (DataColumn c in dt.Columns)
            {

                table.AddCell(new Phrase(c.ColumnName, font5));
            }

            foreach (DataRow r in dt.Rows)
            {
                if (dt.Rows.Count > 0)
                {
                    table.AddCell(new Phrase(r[0].ToString(), font5));
                    table.AddCell(new Phrase(r[1].ToString(), font5));
                    table.AddCell(new Phrase(r[2].ToString(), font5));
                    table.AddCell(new Phrase(r[3].ToString(), font5));
                    table.AddCell(new Phrase(r[4].ToString(), font5));
                }
            }
            document.Add(table);
            document.Close();

            Response.Write(document);
            Response.End();
        } 
    }

Answer 1

正如@Bruno已经回答的那样,您需要使用pageEvents.

请查看以下示例代码:

private void CreatePDF()
{
    string fileName = string.Empty;    
    DateTime fileCreationDatetime = DateTime.Now;    
    fileName = string.Format("{0}.pdf", fileCreationDatetime.ToString(@"yyyyMMdd") + "_" + fileCreationDatetime.ToString(@"HHmmss"));    
    string pdfPath = Server.MapPath(@"~\PDFs\") +   fileName;

    using (FileStream msReport = new FileStream(pdfPath, FileMode.Create))
    {
        //step 1
        using (Document pdfDoc = new Document(PageSize.A4, 10f, 10f, 140f, 10f))
        {
            try
            {
                // step 2
                PdfWriter pdfWriter = PdfWriter.GetInstance(pdfDoc, msReport);
                pdfWriter.PageEvent = new Common.ITextEvents();

                //open the stream 
                pdfDoc.Open();

                for (int i = 0; i < 10; i++)
                {
                    Paragraph para = new Paragraph("Hello world. Checking Header Footer", new Font(Font.FontFamily.HELVETICA, 22));    
                    para.Alignment = Element.ALIGN_CENTER;    
                    pdfDoc.Add(para);    
                    pdfDoc.NewPage();
                }

                pdfDoc.Close();    
            }
            catch (Exception ex)
            {
                //handle exception
            }    
            finally
            { 
            }    
        }    
    }
}

并创建一个名为ITextEvents.cs的类文件并添加以下代码:

public class ITextEvents : PdfPageEventHelper
{    
    // This is the contentbyte object of the writer
    PdfContentByte cb;

    // we will put the final number of pages in a template
    PdfTemplate headerTemplate, footerTemplate;

    // this is the BaseFont we are going to use for the header / footer
    BaseFont bf = null;

    // This keeps track of the creation time
    DateTime PrintTime = DateTime.Now;    

    #region Fields
    private string _header;
    #endregion

    #region Properties
    public string Header
    {
        get { return _header; }
        set { _header = value; }
    }
    #endregion    

    public override void OnOpenDocument(PdfWriter writer, Document document)
    {
        try
        {
            PrintTime = DateTime.Now;
            bf = BaseFont.CreateFont(BaseFont.HELVETICA, BaseFont.CP1252, BaseFont.NOT_EMBEDDED);
            cb = writer.DirectContent;
            headerTemplate = cb.CreateTemplate(100, 100);
            footerTemplate = cb.CreateTemplate(50, 50);
        }
        catch (DocumentException de)
        {    
        }
        catch (System.IO.IOException ioe)
        {    
        }
    }

    public override void OnEndPage(iTextSharp.text.pdf.PdfWriter writer, iTextSharp.text.Document document)
    {
        base.OnEndPage(writer, document);    
        iTextSharp.text.Font baseFontNormal = new iTextSharp.text.Font(iTextSharp.text.Font.FontFamily.HELVETICA, 12f, iTextSharp.text.Font.NORMAL, iTextSharp.text.BaseColor.BLACK);    
        iTextSharp.text.Font baseFontBig = new iTextSharp.text.Font(iTextSharp.text.Font.FontFamily.HELVETICA, 12f, iTextSharp.text.Font.BOLD, iTextSharp.text.BaseColor.BLACK);    
        Phrase p1Header = new Phrase("Sample Header Here", baseFontNormal);

        //Create PdfTable object
        PdfPTable pdfTab = new PdfPTable(3);

        //We will have to create separate cells to include image logo and 2 separate strings
        //Row 1
        PdfPCell pdfCell1 = new PdfPCell();
        PdfPCell pdfCell2 = new PdfPCell(p1Header);
        PdfPCell pdfCell3 = new PdfPCell();
        String text = "Page " + writer.PageNumber + " of ";    

        //Add paging to header
        {
            cb.BeginText();
            cb.SetFontAndSize(bf, 12);
            cb.SetTextMatrix(document.PageSize.GetRight(200), document.PageSize.GetTop(45));
            cb.ShowText(text);
            cb.EndText();
            float len = bf.GetWidthPoint(text, 12);
            //Adds "12" in Page 1 of 12
            cb.AddTemplate(headerTemplate, document.PageSize.GetRight(200) + len, document.PageSize.GetTop(45));
        }
        //Add paging to footer
        {
            cb.BeginText();
            cb.SetFontAndSize(bf, 12);
            cb.SetTextMatrix(document.PageSize.GetRight(180), document.PageSize.GetBottom(30));
            cb.ShowText(text);
            cb.EndText();
            float len = bf.GetWidthPoint(text, 12);
            cb.AddTemplate(footerTemplate, document.PageSize.GetRight(180) + len, document.PageSize.GetBottom(30));
        }

        //Row 2
        PdfPCell pdfCell4 = new PdfPCell(new Phrase("Sub Header Description", baseFontNormal));

        //Row 3 
        PdfPCell pdfCell5 = new PdfPCell(new Phrase("Date:" + PrintTime.ToShortDateString(), baseFontBig));
        PdfPCell pdfCell6 = new PdfPCell();
        PdfPCell pdfCell7 = new PdfPCell(new Phrase("TIME:" + string.Format("{0:t}", DateTime.Now), baseFontBig));    

        //set the alignment of all three cells and set border to 0
        pdfCell1.HorizontalAlignment = Element.ALIGN_CENTER;
        pdfCell2.HorizontalAlignment = Element.ALIGN_CENTER;
        pdfCell3.HorizontalAlignment = Element.ALIGN_CENTER;
        pdfCell4.HorizontalAlignment = Element.ALIGN_CENTER;
        pdfCell5.HorizontalAlignment = Element.ALIGN_CENTER;
        pdfCell6.HorizontalAlignment = Element.ALIGN_CENTER;
        pdfCell7.HorizontalAlignment = Element.ALIGN_CENTER;    

        pdfCell2.VerticalAlignment = Element.ALIGN_BOTTOM;
        pdfCell3.VerticalAlignment = Element.ALIGN_MIDDLE;
        pdfCell4.VerticalAlignment = Element.ALIGN_TOP;
        pdfCell5.VerticalAlignment = Element.ALIGN_MIDDLE;
        pdfCell6.VerticalAlignment = Element.ALIGN_MIDDLE;
        pdfCell7.VerticalAlignment = Element.ALIGN_MIDDLE;    

        pdfCell4.Colspan = 3;  

        pdfCell1.Border = 0;
        pdfCell2.Border = 0;
        pdfCell3.Border = 0;
        pdfCell4.Border = 0;
        pdfCell5.Border = 0;
        pdfCell6.Border = 0;
        pdfCell7.Border = 0;    

        //add all three cells into PdfTable
        pdfTab.AddCell(pdfCell1);
        pdfTab.AddCell(pdfCell2);
        pdfTab.AddCell(pdfCell3);
        pdfTab.AddCell(pdfCell4);
        pdfTab.AddCell(pdfCell5);
        pdfTab.AddCell(pdfCell6);
        pdfTab.AddCell(pdfCell7);

        pdfTab.TotalWidth = document.PageSize.Width - 80f;
        pdfTab.WidthPercentage = 70;
        //pdfTab.HorizontalAlignment = Element.ALIGN_CENTER;    

        //call WriteSelectedRows of PdfTable. This writes rows from PdfWriter in PdfTable
        //first param is start row. -1 indicates there is no end row and all the rows to be included to write
        //Third and fourth param is x and y position to start writing
        pdfTab.WriteSelectedRows(0, -1, 40, document.PageSize.Height - 30, writer.DirectContent);
        //set pdfContent value

        //Move the pointer and draw line to separate header section from rest of page
        cb.MoveTo(40, document.PageSize.Height - 100);
        cb.LineTo(document.PageSize.Width - 40, document.PageSize.Height - 100);
        cb.Stroke();

        //Move the pointer and draw line to separate footer section from rest of page
        cb.MoveTo(40, document.PageSize.GetBottom(50) );
        cb.LineTo(document.PageSize.Width - 40, document.PageSize.GetBottom(50));
        cb.Stroke();
    }

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

        headerTemplate.BeginText();
        headerTemplate.SetFontAndSize(bf, 12);
        headerTemplate.SetTextMatrix(0, 0);
        headerTemplate.ShowText((writer.PageNumber - 1).ToString());
        headerTemplate.EndText();

        footerTemplate.BeginText();
        footerTemplate.SetFontAndSize(bf, 12);
        footerTemplate.SetTextMatrix(0, 0);
        footerTemplate.ShowText((writer.PageNumber - 1).ToString());
        footerTemplate.EndText();  
    }
}

我希望它有所帮助!

Answer 2

我们不再讨论iTextSharp了.您正在使用iText 5 for .NET.目前的版本是针对.NET的iText 7.

过时的答案:

在AddHeader已被弃用很久以前和iTextSharp的已被删除.现在使用页面事件完成添加页眉和页脚.这些示例是使用Java编写的,但您可以在此处和此处找到示例的C#端口(滚动到页面底部以获取.cs文件的链接).

请务必阅读文档.许多开发人员在你面前犯下的一个常见错误就是添加了内容OnStartPage.你应该只添加内容OnEndPage.显而易见的是,您需要在绝对坐标处添加内容(例如使用ColumnText),并且需要通过正确定义文档的边距来为页眉和页脚保留足够的空间.

更新的答案:

如果您不熟悉iText,则应使用iText 7并使用事件处理程序添加页眉和页脚.请参阅iText 7 Jump-Start Tutorial for .NET的第3章.

如果你有PdfDocumentiText 7,你可以添加一个事件处理程序:

PdfDocument pdf = new PdfDocument(new PdfWriter(dest));
pdf.addEventHandler(PdfDocumentEvent.END_PAGE, new MyEventHandler());

这是在绝对位置添加文本的难点示例(使用PdfCanvas):

protected internal class MyEventHandler : IEventHandler {
    public virtual void HandleEvent(Event @event) {
        PdfDocumentEvent docEvent = (PdfDocumentEvent)@event;
        PdfDocument pdfDoc = docEvent.GetDocument();
        PdfPage page = docEvent.GetPage();
        int pageNumber = pdfDoc.GetPageNumber(page);
        Rectangle pageSize = page.GetPageSize();
        PdfCanvas pdfCanvas = new PdfCanvas(page.NewContentStreamBefore(), page.GetResources(), pdfDoc);
        //Add header
        pdfCanvas.BeginText()
            .SetFontAndSize(C03E03_UFO.helvetica, 9)
            .MoveText(pageSize.GetWidth() / 2 - 60, pageSize.GetTop() - 20)
            .ShowText("THE TRUTH IS OUT THERE")
            .MoveText(60, -pageSize.GetTop() + 30)
            .ShowText(pageNumber.ToString())
            .EndText();
        pdfCanvas.release();
    }
}

这是一种稍微高级的方式,使用Canvas:

protected internal class MyEventHandler : IEventHandler {
    public virtual void HandleEvent(Event @event) {
        PdfDocumentEvent docEvent = (PdfDocumentEvent)@event;
        PdfDocument pdfDoc = docEvent.GetDocument();
        PdfPage page = docEvent.GetPage();
        int pageNumber = pdfDoc.GetPageNumber(page);
        Rectangle pageSize = page.GetPageSize();
        PdfCanvas pdfCanvas = new PdfCanvas(page.NewContentStreamBefore(), page.GetResources(), pdfDoc);
        //Add watermark
        Canvas canvas = new Canvas(pdfCanvas, pdfDoc, page.getPageSize());
        canvas.setFontColor(Color.WHITE);
        canvas.setProperty(Property.FONT_SIZE, 60);
        canvas.setProperty(Property.FONT, helveticaBold);
        canvas.showTextAligned(new Paragraph("CONFIDENTIAL"),
            298, 421, pdfDoc.getPageNumber(page),
            TextAlignment.CENTER, VerticalAlignment.MIDDLE, 45);
        pdfCanvas.release();
    }
}

还有其他方法可以在绝对位置添加内容.它们在不同的iText书籍中有所描述.

Answer 3

对于 iTextSharp 4.1.6，作为LGPL许可的 iTextSharp 的最后一个版本，Alvaro Patiño提供的解决方案既简单又有效。

因为文档有点稀缺，我想用这个可用于更改页眉和页脚外观的代码片段来扩展他的答案。默认情况下，它们有一个相当大的字体大小和一个粗边框，许多人想要改变。

// Parameters passed on to the function that creates the PDF 
String headerText = "Your header text";
String footerText = "Page";

// Define a font and font-size in points (plus f for float) and pick a color
// This one is for both header and footer but you can also create seperate ones
Font fontHeaderFooter = FontFactory.GetFont("arial", 8f);
fontHeaderFooter.Color = Color.GRAY;

// Apply the font to the headerText and create a Phrase with the result
Chunk chkHeader = new Chunk(headerText, fontHeaderFooter);
Phrase p1 = new Phrase(chkHeader);

// create a HeaderFooter element for the header using the Phrase
// The boolean turns numbering on or off
HeaderFooter header = new HeaderFooter(p1, false);

// Remove the border that is set by default
header.Border = Rectangle.NO_BORDER;
// Align the text: 0 is left, 1 center and 2 right.
header.Alignment = 1;

// add the header to the document
document.Header = header;

// The footer is created in an similar way

// If you want to use numbering like in this example, add a whitespace to the
// text because by default there's no space in between them
if (footerText.Substring(footerText.Length - 1) != " ") footerText += " ";

Chunk chkFooter = new Chunk(footerText, fontHeaderFooter);
Phrase p2 = new Phrase(chkFooter);

// Turn on numbering by setting the boolean to true
HeaderFooter footer = new HeaderFooter(p2, true);
footer.Border = Rectangle.NO_BORDER;
footer.Alignment = 1;

document.Footer = footer;

// Open the Document for writing and continue creating its content
document.Open();

有关更多信息，请查看使用 iTextSharp和iTextSharp创建 PDF - 使用块、短语和段落添加文本。GitHub 上的源代码也可能有用。

Answer 4

这个问题的答案虽然是正确的,却非常复杂.它不需要那么多代码就可以在页眉/页脚中显示文本.这是一个向页眉/页脚添加文本的简单示例.

当前版本的iTextSharp通过实现由IPdfPageEvent接口定义的回调类来工作.根据我的理解,在OnStartPage方法中添加东西不是一个好主意,所以我将使用OnEndPage页面方法.事件是根据发生的事件触发的PdfWriter

首先,创建一个实现的类IPdfPageEvent.在里面:

public void OnEndPage(PdfWriter writer, Document document)

函数,PdfContentByte通过调用获取对象

PdfContentByte cb = writer.DirectContent;

现在您可以非常轻松地添加文本:

ColumnText ct = new ColumnText(cb);

cb.BeginText();
cb.SetFontAndSize(BaseFont.CreateFont(BaseFont.TIMES_ROMAN, BaseFont.CP1252, BaseFont.NOT_EMBEDDED), 12.0f);
//Note, (0,0) in this case is at the bottom of the document
cb.SetTextMatrix(document.LeftMargin, document.BottomMargin); 
cb.ShowText(String.Format("{0} {1}", "Testing Text", "Like this"));
cb.EndText();

所以OnEndPage功能的全部内容将是:

public void OnEndPage(PdfWriter writer, Document document)
{
    PdfContentByte cb = writer.DirectContent;
    ColumnText ct = new ColumnText(cb);

    cb.BeginText();
    cb.SetFontAndSize(BaseFont.CreateFont(BaseFont.TIMES_ROMAN, BaseFont.CP1252, BaseFont.NOT_EMBEDDED), 12.0f);
    cb.SetTextMatrix(document.LeftMargin, document.BottomMargin);
    cb.ShowText(String.Format("{0} {1}", "Testing Text", "Like this"));
    cb.EndText();

}

这将显示在文档的底部.最后一件事.不要忘记分配IPdfPageEvent这样的:

writter.PageEvent = new PDFEvents();

给PdfWriter写作对象

对于标题,它非常相似.只需翻转SetTextMatrixy坐标:

cb.SetTextMatrix(document.LeftMargin, document.PageSize.Height - document.TopMargin);