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Creating a blank pdf and uploading an image to each page

I am new to file handling in asp.net core 6.0. I want to create a blank pdf and load images from the ImagePath list into it. Using the resources on the internet, I tried to create a blank pdf and throw it into it, but in vain.
I couldn't use pdfReader inside pdfStamper. It was the only resource on the Internet that I found suitable for myself.
Link to the question; Converting Multiple Images into Multiple Pages PDF using itextsharp
How can I do that my code is below.
public static string MainStamping(string docname, List < string > imagePath, string mediaField) {
var config = new ConfigurationBuilder().AddJsonFile("appsettings.json").Build();
var webRootPath = config["AppSettings:urunResimPath"].ToString();
string filename = webRootPath + "\\menupdf\\" + docname + ".pdf";
// yeniisim = yeniisim + filelist.FileName;
// var fileName = "menupdf\\" + yeniisim;
FileStream pdfOutputFile = new FileStream(filename, FileMode.Create);
PdfConcatenate pdfConcatenate = new PdfConcatenate(pdfOutputFile);
PdfReader result = null;
for (int i = 0; i < imagePath.Count; i++) {
result = CreatePDFDocument1(imagePath[i], mediaField);
pdfConcatenate.AddPages(result);
}
pdfConcatenate.Close();
return filename;
}
public static PdfReader CreatePDFDocument1(string imagePath, string mediaField) {
PdfReader pdfReader = null;
//C:\Users\hilal\OneDrive\Belgeler\GitHub\Restaurant\Cafe.Web\wwwroot\assets\barkod-menu
var config = new ConfigurationBuilder().AddJsonFile("appsettings.json").Build();
var webRootPath = config["AppSettings:urunResimPath"].ToString();
string image = webRootPath + "\\barkod-menu\\" + imagePath;
iTextSharp.text.Image instanceImg = iTextSharp.text.Image.GetInstance(image);
MemoryStream inputStream = new MemoryStream();
inputStream.Seek(0, SeekOrigin.Begin); //I don't know what to do here do I need to use it?
pdfReader = new PdfReader(inputStream);
MemoryStream memoryStream = new MemoryStream();
PdfStamper pdfStamper = new PdfStamper(pdfReader, memoryStream);
AcroFields testForm = pdfStamper.AcroFields;
testForm.SetField("MediaField", mediaField);
PdfContentByte overContent = pdfStamper.GetOverContent(1);
IList < AcroFields.FieldPosition > fieldPositions = testForm.GetFieldPositions("ImageField");
if (fieldPositions == null || fieldPositions.Count <= 0) throw new ApplicationException("Error locating field");
AcroFields.FieldPosition fieldPosition = fieldPositions[0];
overContent.AddImage(instanceImg);
pdfStamper.FormFlattening = true;
pdfStamper.Close();
PdfReader resultReader = new PdfReader(memoryStream.ToArray());
pdfReader.Close();
return resultReader;
}
If I want to explain visually, the blank pdf I created will be uploaded in this way. Thank you

The following shows how to create a PDF using iTextSharp (v. 5.5.13.3), and add images to the PDF (one image per page). It's been tested with .NET 6.
Pre-requisite:
Download / install NuGet package iTextSharp (v. 5.5.13.3)
Add the following using statements:
using iTextSharp.text;
using iTextSharp.text.pdf;
using System.IO;
In the code below the PDF is saved to a byte array, instead of a file to allow for more options.
CreatePdfDocument:
public static byte[] CreatePdfDocument(List<string> imagePaths)
{
byte[] pdfBytes;
using (MemoryStream ms = new MemoryStream())
{
using (Document doc = new Document(PageSize.LETTER, 1.0f, 1.0f, 1.0f, 1.0f))
{
using (PdfWriter writer = PdfWriter.GetInstance(doc, ms))
{
//open
doc.Open();
//create a new page for each image
for (int i = 0; i < imagePaths.Count; i++)
{
//add new page
doc.NewPage();
//get image
iTextSharp.text.Image img = iTextSharp.text.Image.GetInstance(imagePaths[i]);
//ToDo: set desired image size
//img.ScaleAbsolute(100.0f, 100.0f);
//center image on page
img.SetAbsolutePosition((PageSize.LETTER.Width - img.ScaledWidth) / 2, (PageSize.LETTER.Height - img.ScaledHeight) / 2);
//add image to page
doc.Add(img);
}
//close
doc.Close();
//convert MemoryStream to byte[]
pdfBytes = ms.ToArray();
}
}
}
return pdfBytes;
}
I've decided that all I want to do is write the PDF to a file. The method below writes the PDF to a file.
CreatePdf:
public static void CreatePdf(string filename, List<string> imagePaths)
{
//create PDF
byte[] pdfBytes = CreatePdfDocument(imagePaths);
//save PDF to file
System.IO.File.WriteAllBytes (filename, pdfBytes);
}
Resources:
How to generate PDF one page one row from datatable using iTextSharp
iTextSharp - Working with images
Center image in pdf using itextsharp
Additional Resources:
iTextSharp: How to resize an image to fit a fix size?

ItextSharp return a corrupted file after editing existing pdf file

I am new to itextSharp. What I am doing is just editing the old file and instead of saving the new file on the server I just want it to download at the time. but unfortunately after editing the file and being downloaded, file display a message cannot open the file. It may be corrupted.
Here is my code.
public FileStreamResult export( int ? id)
{
string pathin = Server.MapPath(Url.Content("~/PDF/input.pdf"));
PdfReader reader = new PdfReader(pathin);
iTextSharp.text.Rectangle size = reader.GetPageSizeWithRotation(1);
Document document = new Document(size);
// open the writer
//FileStream ms = new FileStream(pathout, FileMode.Create, FileAccess.Write);
var ms = new MemoryStream();
PdfWriter writer = PdfWriter.GetInstance(document, ms);
writer.CloseStream = false;
document.Open();
// the pdf content
PdfContentByte cb = writer.DirectContent;
// select the font properties
BaseFont bf = BaseFont.CreateFont(BaseFont.HELVETICA, BaseFont.CP1252, BaseFont.NOT_EMBEDDED);
cb.SetColorFill(BaseColor.DARK_GRAY);
cb.SetFontAndSize(bf, 18f);
// write the text in the pdf content
cb.BeginText();
string text = "this is text";
// put the alignment and coordinates here
cb.ShowTextAligned(1, text, 500, 500, 0);
cb.EndText();
cb.BeginText();
text = "this is my post";
// put the alignment and coordinates here
cb.ShowTextAligned(1, text, 600, 400, 0);
cb.EndText();
// create the new page and add it to the pdf
PdfImportedPage page = writer.GetImportedPage(reader, 1);
cb.AddTemplate(page, 0, 0);
ms.Position = 0;
document.Close();
//ms.Close();
writer.Close();
reader.Close();
return File(ms, "application/pdf","test.pdf");
}
Any help will be really appreciated. :)

You change the position of the memory stream before closing the document:
ms.Position = 0;
document.Close();
As the trailer of the pdf in the result stream is written during the closing of the document, your change of stream position causes the pdf trailer to be written over the pdf header and the stream position thereafter to not be at the start.
Instead first close the document and the reader (the writer implicitly is closed by closing the document) and reset the stream position thereafter:
document.Close();
reader.Close();
ms.Position = 0;
return File(ms, "application/pdf","test.pdf");

The document has no catalog object (meaning: it's an invalid PDF)

I am reading and writing to the same PDF at the same time i am getting error "The document has no catalog object (meaning: it's an invalid PDF)" on this line "PdfReader pdfReader = new PdfReader(inputPdf2);" in the below code snippet.
iTextSharp.text.pdf.PdfCopy pdfCopy = null;
Document finalPDF = new Document();
//pdfReader = null;
FileStream fileStream = null;
int pageCount = 1;
int TotalPages = 20;
try
{
fileStream = new FileStream(finalPDFFile, FileMode.OpenOrCreate, FileAccess.Write);
pdfCopy = new PdfCopy(finalPDF, fileStream);
finalPDF.Open();
foreach (string inputPdf1 in inputPDFFiles)
{
if (File.Exists(inputPdf1))
{
var bytes = File.ReadAllBytes(inputPdf1);
PdfReader pdfReader = new PdfReader(bytes);
fileStream = new FileStream(inputPdf1, FileMode.Open, FileAccess.Write);
var stamper = new PdfStamper(pdfReader, fileStream);
var acroFields = stamper.AcroFields;
stamper.AcroFields.SetField(acrofiled.Key, "Page " + 1+ " of " + 16);
stamper.FormFlattening = true;
stamper.Close();
stamper.Dispose();
fileStream.Close();
fileStream.Dispose();
pdfReader.Close();
pdfReader.Dispose();
}
}
foreach (string inputPdf2 in inputPDFFiles)
{
if (File.Exists(inputPdf2))
{
PdfReader pdfReader = new PdfReader(inputPdf2);
int pageNumbers = pdfReader.NumberOfPages;
for (int pages = 1; pages <= pageNumbers; pages++)
{
PdfImportedPage page = pdfCopy.GetImportedPage(pdfReader, pages);
PdfCopy.PageStamp pageStamp = pdfCopy.CreatePageStamp(page);
pdfCopy.AddPage(page);
}
pdfReader.Close();
pdfReader.Dispose();
}
}
pdfCopy.Close();
pdfCopy.Dispose();
finalPDF.Close();
finalPDF.Dispose();
fileStream.Close();
fileStream.Dispose();
please help me in order to fix issue or give me any alternate approach

In your first loop you overwrite each of your files with a manipulated version like this:
var bytes = File.ReadAllBytes(inputPdf1);
PdfReader pdfReader = new PdfReader(bytes);
fileStream = new FileStream(inputPdf1, FileMode.Open, FileAccess.Write);
var stamper = new PdfStamper(pdfReader, fileStream);
[...]
Using FileMode.Open here is an error. You want to replace the existing file with a new one, and for such a use case you have to use FileMode.Create or FileMode.Truncate.
Using FileMode.Open results in the original file content remaining there and you writing into it. Thus, if your new file content is shorter than the original one (which can happen when flattening a form), your new file keeps a tail segment of the original file. In PDFs there are relevant lookup information at the end, so upon reading this new file the PdfReader finds the lookup information of the old file which don't match the new content anymore at all.
By the way, you create the PdfCopy like this:
fileStream = new FileStream(finalPDFFile, FileMode.OpenOrCreate, FileAccess.Write);
pdfCopy = new PdfCopy(finalPDF, fileStream);
This is wrong for the same reason: If there already is PDF there, FileMode.OpenOrCreate works just like FileMode.Open with the unwanted effects described above.
Thus, you should replace the FileMode values for streams you write to with FileMode.Create.

how read pdf layers and add to another page using itextsharp?

How can I read PDF layers and add them to another page using iTextSharp?
I want to copy layers from one PDF page and move them to another PDF page in C#.
I've tried reading from a PDF layer from one page, but I am unable to copy that layer.
var document = new Document();
FileStream outfile = new FileStream(outPutFilePath, FileMode.Create);
var writer = new PdfCopy(document, outfile);
document.Open();
foreach (var fileName in filesPath)
{
var reader = new PdfReader(fileName);
PdfStamper stamper = new PdfStamper(reader, outfile);
Dictionary<String, PdfLayer> layers = stamper.GetPdfLayers();
//PdfLayer layer = layers.get("Nested layer 1");
//layer.setOn(false);
for (var i = 1; i <= reader.NumberOfPages; i++)
{
var page = writer.GetImportedPage(reader, i);
page.ContentTagged = true;
writer.AddPage(page);
}
stamper.Close();
reader.Close();
}
writer.Close();
document.Close();

I want to watermark a pdf file without creating another pdf file

I want to convert an image to PDF and add a watermark to it. I used iTextSharp to convert it. I successfully converted the image file to pdf but I'm not able to add watermark to it without creating another pdf file.
The code below creates a PDF file and also adds custom attributes,
function watermarkpdf is used to add watermark and pdfname is given as the arguement
foreach (string filenm in Images)
using (var imageStream = new FileStream(filenm, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
{
doc.NewPage();
iTextSharp.text.Image jpeg = iTextSharp.text.Image.GetInstance(filenm);
float width = doc.PageSize.Width;
float height = doc.PageSize.Height;
jpeg.ScaleToFit(width,height);
doc.Add(jpeg);
}
doc.AddHeader("name", "vijay");
watermarkpdf(pdfname);
The watermarkpdf function is given below.
PdfReader pdfReader = new PdfReader(txtpath.Text+"\\pdf\\" + pdfname);
FileStream stream = new FileStream(txtpath.Text + pdfname,FileMode.Open);
PdfStamper pdfStamper = new PdfStamper(pdfReader, stream);
for (int pageIndex = 1; pageIndex <= pdfReader.NumberOfPages; pageIndex++)
{
Rectangle pageRectangle = pdfReader.GetPageSizeWithRotation(pageIndex);
PdfContentByte pdfData = pdfStamper.GetUnderContent(pageIndex);
pdfData.SetFontAndSize(BaseFont.CreateFont(BaseFont.HELVETICA_BOLD, BaseFont.CP1252, BaseFont.NOT_EMBEDDED), 40);
PdfGState graphicsState = new PdfGState();
graphicsState.FillOpacity = 0.4F;
pdfData.SetGState(graphicsState);
pdfData.SetColorFill(BaseColor.BLUE);
pdfData.BeginText();
pdfData.ShowTextAligned(Element.ALIGN_CENTER, "SRO-Kottarakkara", pageRectangle.Width / 2, pageRectangle.Height / 2, 45);
pdfData.EndText();
}
pdfStamper.Close();
stream.Close();

iTextSharp doesn't support "in-place editing" of files, only reading existing files and creating new files. The problem is that it would have to write to something that is being written to which could be very problematic.
However, instead of using a file you can create your image in a MemoryStream, grab the bytes from that and pipe that to the PdfReader, all with minimal changes to your code. All of the PDF writing functions that take files actually work with the abstract Stream class and which MemoryStream inherits from so they can be used interchangeably. Below is some basic code that should show you what I'm talking about. I don't have an IDE currently so there might be a typo or two but for the most part it should work.
//Image part
//We will dump the bytes from the memory stream to the variable below later
byte[] bytes;
using (MemoryStream ms = new MemoryStream()){
Document doc = new Document(PageSize.LETTER);
PdfWriter writer = PdfWriter.GetInstance(doc, ms);
doc.Open();
//foreach (string filenm in Images)
//...
doc.Close();
//Dump the bytes, make sure to use ToArray() and not GetBuffer()
bytes = ms.ToArray();
}
//Watermark part
//Read from our bytes
PdfReader pdfReader = new PdfReader(bytes);
FileStream stream = new FileStream(txtpath.Text + pdfname,FileMode.Open);
//...