Set the position of a text or an image in a pdf using itextsharp(C#/asp.net)

Question

I have added an image and some text in the pdf using iTextSharp. However, I would like to position my image and text at specific position in the pdf. How do I do it?

So far I tried,

img.SetAbsolutePosition(10000f,10000f);

But it is not working. Here is my complete code for generating the pdf,

 private void generatepdf(byte[] byteImage)
  {


    //byte[] imageBytes = Convert.FromBase64String(base64);

    string text1= "Some Text";
    iTextSharp.text.Image image =   iTextSharp.text.Image.GetInstance(byteImage);
    image.ScalePercent(0.3f * 100);
    string logopath = Server.MapPath("~/images/img1.png");
    iTextSharp.text.Image img = iTextSharp.text.Image.GetInstance(logopath);
    img.SetAbsolutePosition(1000f,1000f);
    img.ScaleAbsolute(1500f, 0f);
    img.ScalePercent(0.5f*100);
    Paragraph ShopName = new Paragraph(text1);
    Paragraph id = "Some Text";

    using (System.IO.MemoryStream memoryStream = new System.IO.MemoryStream())
    {
        Document document = new Document(PageSize.A4, 188f, 88f, 5f, 10f);
        PdfWriter writer = PdfWriter.GetInstance(document, memoryStream);
        document.Open();
        document.Add(img);
        document.Add(ShopName);
        document.Add(image);
        document.Add(id);
        document.Close();
        byte[] bytes = memoryStream.ToArray();
        memoryStream.Close();

        Response.Clear();
        Response.ContentType = "application/pdf";
        Response.AddHeader("Content-Disposition", "attachment; filename=QRCode.pdf");
        Response.ContentType = "application/pdf";
        Response.Buffer = true;
        Response.Cache.SetCacheability(HttpCacheability.NoCache);
        Response.BinaryWrite(bytes);
        Response.End();
    }

 }

Answer 1

If you tried img.SetAbsolutePosition(10000f,10000f); then your image is way out of the visible area of the PDF. You are creating your Document like this:

Document document = new Document(PageSize.A4, 188f, 88f, 5f, 10f);

This means that the size of the page is 595 x 842 user units. Using x = 10000 and y = 10000 doesn't fit inside a rectangle of 595 x 842.

Please try:

img.SetAbsolutePosition(0,0);

When you use these coordinates, the lower-left corner of the image will coincide with the lower-left corner of the page.

Please consult the official iText documentation and search for coordinate system. See for instance:

• How should I interpret the coordinates of a rectangle in PDF?
• Where is the origin (x,y) of a PDF page?
• ...

This will help you find how to define the coordinates for the SetAbsolutePosition() method.

Update:

You are also asking about adding text at absolute positions. Here we have to make the distinction between a single line of text and a block of text. See also the section Absolute positioning of text on the official web site.

A single line of text:

See for instance How to position text relative to page? and you'll find the showTextAligned() method:

ColumnText.showTextAligned(canvas, Element.ALIGN_CENTER,
    new Phrase("Some text"), 100, 100, 0);

Please make sure that you read other examples to so that you discover what the canvas object is about.

A block of text:

Take a look at How to add text inside a rectangle?

ColumnText ct = new ColumnText(cb);
ct.SetSimpleColumn(rect);
ct.AddElement(new Paragraph("This is the text added in the rectangle"));
ct.Go();

Please take a look at the full example to find out what cb and rect are about.