将PDF与iTextSharp合并：javascript丢失

Question

I have two forms pdf that I have to merge programmatically. These 2 documents have javascript embedded and buttons to switch texts between three different languages (french, german, italian). Plus they are plenty AcroForm formfields. There is a javascript function that detects the app language and displays the document in the general user interface language.

When I merge using pdfSmartCopy, the result is a pdf document displaying the three languages simultaneously. I've seen that there is no javascript anymore in the merged document. I've tried to add Javascript manually :

Document doc = new Document();
PdfCopy copy = new PdfSmartCopy(doc, new FileStream(destFileName, FileMode.Create));
copy.SetMergeFields();
doc.Open();
foreach (PdfReader r in listPdfSource)
{
    copy.AddDocument(r);
    PdfAction action = PdfAction.JavaScript(r.JavaScript, copy);
    copy.AddJavaScript(action);
}
doc.Close();

But the document still displays the three languages and the buttons don't work. I've tried to look for XFA part but there is none. Is there a way to keep the js functionnalities of the original documents and inject them in the merged result?

EDIT

Thank you for the OCG tip. I've tried the following :

Dictionary<string, PdfLayer> layers = stamper.GetPdfLayers();
foreach (KeyValuePair<string, PdfLayer> layer in layers)
{
    Console.WriteLine(layer.Key);
}

And It gave me a very interesting list containing fre, ger, ita among other things. For a single original document I tested the way to "disable" a layer by using :

layer.On = false;
// or
layer.OnPanel = false;
// and
layer.View = false;

Only the third one gave a result. Then I made the following:

Document doc = new Document();
PdfCopy copy = new PdfSmartCopy(doc, new FileStream(tempFileName, FileMode.Create));
copy.SetMergeFields();
doc.Open();
foreach (PdfReader r in listPdfSource)
{
    copy.AddDocument(r);
    PdfAction action = PdfAction.JavaScript(r.JavaScript, copy);
    copy.AddJavaScript(action);
}
doc.Close();
//re-open the document and create a stamper for getting the layers
PdfReader reader = new PdfReader(tempFileName);
PdfStamper stamper = new PdfStamper(reader, new FileStream(destFileName, FileMode.Create));
stamper.GetPdfLayers()["ger"].View = false;
stamper.GetPdfLayers()["ita"].View = false;
stamper.Close();

But of course it doesn't work because the new document's layers list is empty! It worked for a single original document. Then I tried to make this manipulation for each original document separately and merge them after. But it's still displaying the three languages simultaneously.

EDIT 2

I was asked by @Bruno Lowagie to share the original documents :

http://www.filedropper.com/source1

http://www.filedropper.com/source2

(I need a reputation of 10 to post more than 2 links? You can find the link for the merged document in the comments)

I really hope that a specialist can give me the way where to look further. As I understood it's a question about OCG and JS involved at document level. How to retrieve and apply them to the new merged document.

Answer 1

It might be worth checking out the following library: http://www.nrecosite.com/pdf_generator_net.aspx

Its free and it supports JS and HTML5, and you can bulk combine pdfs into one file. I have used it in the past to hide certain elements with JS for printing purposes .