Merge PDF file at specific page or location ASP.NET - asp.net

Question

We have ASP.NET app in which, I am trying to merge two PDF files and we are currently using BCL easyPDF7 library. I am trying to merge new file at specific location or page (for example after 3rd page in main document) But I found that Merge in this library simply appends the file in the end.
We have decided to go for new tool PDF4NET and I observed from the sample codes of PDF4NET that they also provide Merge functionality which appends the document in the end.
Is there any way we can achieve this ? (either through PDF4NET or BCL easyPDF7 ) Please share your views.

Answer 1

I've used iTextSharp before to do this and basically create a new output pdf and then read in the new documents and loop through the pages adding the pages to the new output document. This will even maintain pagesize and orientation information for each page.
Here is the code that adds the pdf to the output one:
int pc = pdfReader.NumberOfPages;
int p, rotation;
Rectangle box;
PdfImportedPage page;
for (p = 0; p < pc; p++) {
pageNo++;
page = pdfWriter.GetImportedPage(pdfReader, p + 1);
rotation = pdfReader.GetPageRotation(p + 1);
box = pdfReader.GetPageSizeWithRotation(p + 1);
outputDoc.SetPageSize(box);
outputDoc.NewPage();
if ((rotation == 90) || (rotation == 270)) {
pdfContentByte.AddTemplate(page, 0, -1.0f, 1.0f, 0, 0, box.Height);
} else {
pdfContentByte.AddTemplate(page, 1.0f, 0, 0, 1.0f, 0, 0);
}
}
pdfReader.Close();
In this example pdfReader is an instance of PdfReader class referencing the source pdf to add. This can be by either file, stream or byte array. pdfWriter is a new instance of PdfWriter class that is the output content.
I know it isn't using PDF4NET or BCL easyPDF7 but hopefully it will help.

Answer 2

I got it working by extracting pages and creating a new file. I extracted the pages from main file upto index which is page number at which I want to insert my second file.
Hope it helps who are dealing with PDF4NET and want merge file at specific page number.
private string MergeFiles(string mainfile, string attachment, string path, int index)
{
var newFile = #"C:\Test\PDF\NewInsertedAt2.pdf";
int mainFilePages, attachFilePages, i, j, k;
PDFFile mainFile = PDFFile.FromFile(mainfile);
PDFFile attachFile = PDFFile.FromFile(attachment);
PDFImportedPage ip = null;
PDFDocument doc = new PDFDocument();
mainFilePages = mainFile.PagesCount;
attachFilePages = attachFile.PagesCount;
for (i = 0; i < index; i++)
{
ip = mainFile.ExtractPage(i);
doc.Pages.Add(ip);
}
for (j = 0; j < attachFilePages; j++)
{
ip = attachFile.ExtractPage(j);
doc.Pages.Add(ip);
}
for (k = i; k < mainFilePages; k++)
{
ip = mainFile.ExtractPage(k);
doc.Pages.Add(ip);
}
doc.Save(newFile);
mainFile.Close();
attachFile.Close();
return newFile;
}