Develop Reference

save as iText.Layout.Element.Image in folder

i want to save pdf page as image but no success. i am able to create iText.Layout.Element.Image from pdf with itext7 but stuck here
using var pdfreader = new PdfReader("../../../documents/valid.pdf");
PdfDocument origPdf = new PdfDocument(pdfreader);
PdfPage origPage = origPdf.GetPage(1);
using var stream = new MemoryStream();
using var pdfwriter = new PdfWriter(stream);
PdfDocument pdf = new PdfDocument(pdfwriter);
Document document = new Document(pdf);
PdfFormXObject pageCopy = origPage.CopyAsFormXObject(pdf);
Image image = new Image(pageCopy);
// want to save this image

The iText 7 Image class is (according to JavaDocs) a layout element that represents an image for inclusion in the document model. It essentially can wrap arbitrary contents to be added to the contents of some page (or form XObject, ...) in an image like manner. It is not, however, an arbitrary-content-to-bitmap converter.
If you want to render a page as a bitmap using iText 7 components, consider using the iText 7 Core add-on pdfRender.

Why is my copied PDF file sized incorrect?

I need to remove the first few pages of a PDF file. Apparently, the easiest way to do that is to create a copy of it and not duplicate the unwanted pages. This works, but they look a lot smaller than they should. Any ideas?
How it should look
How it actually looks
private static void ClipSpecificPDF(string input, string output, int pagesToCut)
{
PdfReader myReader = new PdfReader(input);
using (FileStream fs = new FileStream(output, FileMode.Create, FileAccess.Write, FileShare.None))
{
using (Document doc = new Document())
{
using (PdfWriter myWriter = PdfWriter.GetInstance(doc, fs))
{
//Open the desitination for writing
doc.Open();
//Loop through each page that we want to keep
for (int i = pagesToCut; i < myReader.NumberOfPages; i++)
{
//Add a new blank page to destination document
var PS = myReader.GetPageSizeWithRotation(i);
myWriter.SetPageSize(PS);
doc.NewPage();
//Extract the given page from our reader and add it directly to the destination PDF
myWriter.DirectContent.AddTemplate(myWriter.GetImportedPage(myReader, i + 1), 0, 0);
}
//Close our document
doc.Close();
}
}
}
}

The problem you describe is explained in the FAQ. For instance in the answer to the questions:
How to merge documents correctly?
Why does the function to concatenate / merge PDFs cause issues in some cases?
Using PdfWriter to manipulate PDF documents is a very bad idea. Read chapter 6 of my book to discover why this is a bad idea, and take a look at Table 6.1 to find out which class is a better fit.
In the same chapter, you'll find the SelectPages example. Suppose that you want to create a new PDF containing only page 4 to 8. In that case, you simply use the SelectPages() method and PdfStamper:
PdfReader reader = new PdfReader(src);
reader.SelectPages("4-8");
PdfStamper stamper = new PdfStamper(reader, new FileStream(dest, FileMode.Create, FileAccess.Write));
stamper.Close();
reader.Close();
By using PdfReader, the page size is preserved, as well as any of the interactive features that may be present.
Your approach is bad because you do not respect the original page size: you copy a document with letter (?) format to a document with A4 pages. If the origin of the page doesn't correspond with the lower-left corner, parts of your document will be invisible. If there are interactive features in your PDF, they will be lost. Of all the possible examples you could have followed, you picked the worst one...

Drawing on PDF using ITextSharp, without creating a new PDF

i try to draw simple shapes (rectangles, circles..) on an existing PDF using ITextSharp, without having to create a new PDF. I found a post who talk about this issue (itextsharp modify existing pdf (no new source pdf) and add watermark) and i would like to know if anybody could tell me more about it.
my aim is to modify a pdf by adding a circle on it, the current solution involve the creation of a new PDF (Itextsharp). Is it possible to add a circle on a PDF without creating a new one ?
Thank you.
J.

You can't read a file and write to it simultaneously. Think of how Word works: you can't open a Word document and write directly to it. Word always creates a temporary file, writes the changes to it, then replaces the original file with it and then throws away the temporary file.
You can do that too:
read the original file with PdfReader,
create a temporary file for PdfStamper, and when you're done,
replace the original file with the temporary file.
Or:
read the original file into a byte[],
create PdfReader with this byte[], and
use the path to the original file for PdfStamper.
This second option is more dangerous, as you'll lose the original file if you do something that causes an exception in PdfStamper.
As for adding content with PdfStamper, please take a look at the section entitled "Manipulating existing PDFs" in the free ebook The Best iText Questions on StackOverflow. You'll find questions such as:
How to add a watermark to a PDF file?
How do I insert a hyperlink to another page with iTextSharp in an existing PDF?
iText - How to stamp image on existing PDF and create an anchor
...
All of these examples add content by creating a PdfContentByte instance like this:
PdfContentByte canvas = stamper.getOverContent(pagenumber);
It's this canvas you need to use when drawing a circle on the page with page number pagenumber. It is important that you use the correct coordinates when you do this. That's explained here: How to position text relative to page using iText?
Update:
Json posted the following code in the comments:
string oldFile = #"C:\Users\ae40394\Desktop\hello.pdf";
string newFile = #"C:\Users\ae40394\Desktop\NEW.pdf";
// creating a reader with the original PDF
PdfReader reader = new PdfReader(oldFile);
Rectangle rect = reader.GetPageSize(1);
FileStream fs = new FileStream(newFile,FileMode.Create);
using (PdfStamper stamper = new PdfStamper(reader, fs)) {
// modify the pdf content
PdfContentByte cb = stamper.GetOverContent(1);
cb.SetColorStroke(iTextSharp.text.BaseColor.GREEN);
cb.SetLineWidth(5f);
cb.Circle(rect.GetLeft() + 30, rect.GetBottom() + 30 ,20f);
cb.Stroke();
}
reader.Close();
File.Replace(#"C:\Users\ae40394\Desktop\NEW.pdf", #"C:\Users\ae40394\Desktop\hello.pdf", #"C:\Users\ae40394\Desktop\hello.pdf.bac");
I slightly adapted the code, because:
There is no need for a Document object,
The stamper is closed when using is closed,
When the stamper is closed, so is the FileStream
the coordinates of the circle were hard coded. I used the page size to make sure they are made relative to the origin of the coordinate system, although to be sure, you may also want to check if there's a Crop Box.

You CAN read a file and write to it simultaneously.
Here is an example:
private void button4_Click(object sender, EventArgs e)
{
using (PdfReader pdfReader = new PdfReader(new FileStream(pdfInput, FileMode.Open, FileAccess.Read, FileShare.Read)))
{
using (PdfStamper pdfStamper = new PdfStamper(pdfReader, new FileStream(pdfInput, FileMode.Open, FileAccess.Write, FileShare.None)))
{
PdfContentByte canvas = pdfStamper.GetUnderContent(1);
canvas.SetColorFill(BaseColor.YELLOW);
canvas.Rectangle(36, 786, 66, 16);
canvas.Fill();
}
}
// PDF Datei im Anschluss anzeigen/öffnen
System.Diagnostics.Process.Start(pdfInput);
}

string oldFile = #"C:\...6166-21.pdf";
string newFile = #"C:\...NEW.pdf";
// open the reader
PdfReader reader = new PdfReader(oldFile);
Rectangle size = reader.GetPageSizeWithRotation(1);
Document document = new Document(size);
FileStream fs = new FileStream(newFile, FileMode.Create, FileAccess.Write);
PdfWriter writer = PdfWriter.GetInstance(document, fs);
document.Open();
// the pdf content
PdfContentByte cb = writer.DirectContent;
cb.SetColorStroke(iTextSharp.text.BaseColor.GREEN);
cb.Circle(150f, 150f, 50f);
cb.Stroke();
// create the new page and add it to the pdf
PdfImportedPage page = writer.GetImportedPage(reader, 1);
cb.AddTemplate(page, 0, 0);
// close the streams and voilá the file should be changed :)
document.Close();
fs.Close();
writer.Close();
reader.Close();

Opening a second PdfReader within a using block in iTextSharp

I have the following code which opens a PDF and adds some text and images. At one point, I am opening a second PDF, wrapping it in an Image and adding it to the PDF. After the operation completes successfully, I want to delete the second PDF (the one I wrapped in an Image). The problem is that the file is now locked until I reset my ASP.NET application.
In the GetImageFromPdf method, you can see that I am creating a second PdfReader instance. The problem is, if I close this reader, the reader in my Create method is also closed! Am I doing something wrong? Is there another way to achieve my goal?
Here is the relevant code:
public void Create(string outputFilePath, bool preview = false)
{
using (PdfReader reader = new PdfReader(FilePath))
{
using (PdfStamper stamper = new PdfStamper(reader, new FileStream(outputFilePath, FileMode.Create)))
{
PdfContentByte canvas = stamper.GetOverContent(1);
...
AddMap(canvas, stamper);
}
}
}
...
private void AddMap(PdfContentByte Canvas, PdfStamper stamper)
{
Image ImageWrapper = GetImageFromPdf(stamper.Writer, _MapFilePath);
//set the position and scale the image
ImageWrapper.ScaleAbsolute(152.5f, 152.5f);
ImageWrapper.SetAbsolutePosition(58.5f, 197.5f);
Canvas.AddImage(ImageWrapper);
}
...
public Image GetImageFromPdf(PdfWriter Writer, string MapFilePath)
{
//since vector images are not supported natively by iTextSharp
//we have saved the location maps as PDF (originally in eps format)
//we use GetImportedPage to import the file, and wrap it in an Image object so we can scale it
//If I close this reader, the reader in the Create method is closed as well
PdfReader reader = new PdfReader(MapFilePath);
PdfImportedPage ImportedPage = Writer.GetImportedPage(reader, 1);
return Image.GetInstance(ImportedPage);
}

Try this
using (PdfReader reader = new PdfReader(FilePath),PdfReader reader1 = new PdfReader(MapFilePath))
{
pass that reader1 object to AddMap method.
}

How to add a PDF form field (or a text) and link in the page bottom of a page of an existing PDF document using iTextSharp?

I have an existing PDF document named as aa.pdf. This PDF document has 3 pages. I'd like to add a PDF form field (or a text) at the page bottom of the first page in aa.pdf using iTextSharp.
Meanwhile, I also hope that the PDF form field added (or the text added) can link into another page of aa.pdf. For example, after I click the PDF form field (or the text) located in the first page of aa.pdf,this PDF document skips into the second page.
How can I realize the aboved functionalities using iTextSharp?
Thanks.

To create links within a PDF you use a PdfAction which can be set on a Chunk which can optionally be added to a Paragraph. There are several different types of actions that you can choose from, the two that you are probably interested in are the NEXTPAGE action and/or the GotoLocalPage action. The first item does what it says and goes to the next page. This one is nice because you don't have to worry about figuring out what page number you are on. The second item allows you to specify the specific page number to go to. In its simplest form you can do:
Chunk ch = new Chunk("Go to next page").SetAction(new PdfAction(PdfAction.NEXTPAGE));
This creates a Chunk that you can add in whatever way you want. When working with an existing PDF there's several different ways to add text to a page. One way it to use a ColumnText object which has a method called SetSimpleColumn that allows you to define a simple rectangle that you can add elements to.
Lastly, PDF readers don't automatically treat links differently within a PDF except to give a different cursor when hovering. More specifically, unlike a webpage where hyperlinks are turned a different color, PDFs don't change the color of links unless you tell them to, so this should be kept in mind when creating them. Also, when modifying a PDF you generally never want to overwrite the existing PDF during the process because that would be writing to something that your reading from. Sometimes it works, more often then not it breaks, sometimes subtly. Instead, write to a second file and when you are completely done, erase the first file and rename the second file.
The code below is a full working C# 2010 WinForms app targeting iTextSharp 5.1.2.0. The first part of the code creates a sample PDF called "aa.pdf" on the desktop. If you already have that file you can comment this section out but its in here so others can reproduce this example. The second part creates a new file called "bb.pdf" based on "aa.pdf". It adds two text links to the bottom of the first page. The first link advances the PDF to just the next page while the second link advances the PDF to a specific page number. See the comments in the code for specific implementation details.
using System;
using System.IO;
using System.Windows.Forms;
using iTextSharp.text;
using iTextSharp.text.pdf;
namespace WindowsFormsApplication1 {
public partial class Form1 : Form {
public Form1() {
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e) {
//Files that we'll be working with
string inputFile = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Desktop), "aa.pdf");
string outputFile = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Desktop), "bb.pdf");
//Create a standard PDF to test with, nothing special here
using (FileStream fs = new FileStream(inputFile, FileMode.Create, FileAccess.Write, FileShare.None)) {
using (Document doc = new Document(PageSize.LETTER)) {
using (PdfWriter writer = PdfWriter.GetInstance(doc, fs)) {
doc.Open();
//Create 10 pages with labels on each page
for (int i = 1; i <= 10; i++) {
doc.NewPage();
doc.Add(new Paragraph(String.Format("This is page {0}", i)));
}
doc.Close();
}
}
}
//For the OP, this is where you would start
//Declare some variables to be used later
ColumnText ct;
Chunk c;
//Bind a reader to the input file
PdfReader reader = new PdfReader(inputFile);
//PDFs don't automatically make hyperlinks a special color so we're specifically creating a blue font to use here
iTextSharp.text.Font BlueFont = FontFactory.GetFont("Arial", 12, iTextSharp.text.Font.NORMAL, iTextSharp.text.BaseColor.BLUE);
//Create our new file
using (FileStream fs = new FileStream(outputFile, FileMode.Create, FileAccess.Write, FileShare.None)) {
//Bind a stamper to our reader and output file
using (PdfStamper stamper = new PdfStamper(reader, fs)) {
Chunk ch = new Chunk("Go to next page").SetAction(new PdfAction(PdfAction.NEXTPAGE));
//Get the "over" content for page 1
PdfContentByte cb = stamper.GetOverContent(1);
//This example adds a link that goes to the next page
//Create a ColumnText object
ct = new ColumnText(cb);
//Set the rectangle to write to
ct.SetSimpleColumn(0, 0, 200, 20);
//Add some text and make it blue so that it looks like a hyperlink
c = new Chunk("Go to next page", BlueFont);
//Set the action to go to the next page
c.SetAction(new PdfAction(PdfAction.NEXTPAGE));
//Add the chunk to the ColumnText
ct.AddElement(c);
//Tell the system to process the above commands
ct.Go();
//This example add a link that goes to a specific page number
//Create a ColumnText object
ct = new ColumnText(cb);
//Set the rectangle to write to
ct.SetSimpleColumn(200, 0, 400, 20);
//Add some text and make it blue so that it looks like a hyperlink
c = new Chunk("Go to page 3", BlueFont);
//Set the action to go to a specific page number. This option is a little more complex, you also have to specify how you want to "fit" the document
c.SetAction(PdfAction.GotoLocalPage(3, new PdfDestination(PdfDestination.FIT), stamper.Writer));
//Add the chunk to the ColumnText
ct.AddElement(c);
//Tell the system to process the above commands
ct.Go();
}
}
this.Close();
}
}
}