Merging/filling pdf form file with xml data

Question

Let's say I have a pdf form file available at website which is filled by the users and submitted to the server. On the server side (Asp.Net) I would like to merge the data that I receive in xml format with the empty pdf form that was filled and save it.

As I have found there are several possible ways of doing it:

1. Using pdf form created by adobe acrobat and filling it with itextsharp.
2. Using pdf form created by adobe acrobat and filling it with FDF Toolkit .net (which seems to be using itextsharp internally)
3. Usd pdfkt to fill the form.
4. Use pdf form file created with adobe livecycle and merge the data by using Form Data Integration Service

As I have no experience with this kind of task can you advise which option would be better/easier and give some additional tips?

Thank you in advance.

Solution

I would suggest using the 4th approach if possible because it would be cleaner. You would be using solutions specifically tailored for what you are asking to do, but if you don't have the available resources for such a solution I would suggest using the 1st option.

The 1st option is what I have recently dove into. I have found it relatively painless to implement.

Option 1 is possible if the following applies:

1. You have control of development of PDF forms.
2. You have control of formating xml data
3. You have can live with having uncompressed (fastweb=false) PDF files

Example of implementation:

1. Using Adobe Acrobat to generate a PDF form. Tip: Use Adobe Native Fonts when generating the forms. For each control you add that is not a native font it will import the font used and bloat the file when it is not compressed, and to my knowledge ITextSharp currently does not produce compressed PDFs.

2. Using ITextSharp Library to combine XML data with the PDF form to generate a populated document. Tip: to manually populate a PDF form from xml you must map xml values to control names in the PDF form and match them by page as shown in the example below.

   using (MemoryStream stream = GeneratePDF(m_FormsPath, oXmlData))
   {
         byte[] bytes = stream.ToArray();
         Response.ContentType = "application/pdf";
         Response.BinaryWrite(bytes);
         Response.End();
   }
   
   // <summary>
   // This method combines pdf forms with xml data
   // </summary>
   // <param name="m_FormName">pdf form file path</param>
   // <param name="oData">xml dataset</param>
   // <returns>memory stream containing the pdf data</returns>
   private MemoryStream GeneratePDF(string m_FormName, XmlDocument oData)
   {
   PdfReader pdfTemplate;
   PdfStamper stamper;
   PdfReader tempPDF;
   Document doc;
   MemoryStream msTemp;
   PdfWriter pCopy;
   MemoryStream msOutput = new MemoryStream();
   
   pdfTemplate = new PdfReader(m_FormName);
   
   doc = new Document();
   pCopy = new PdfCopy(doc, msOutput);
   
   pCopy.AddViewerPreference(PdfName.PICKTRAYBYPDFSIZE, new PdfBoolean(true));
   pCopy.AddViewerPreference(PdfName.PRINTSCALING, PdfName.NONE);
   
   doc.Open();
   
   for (int i = 1; i < pdfTemplate.NumberOfPages + 1; i++)
   {
       msTemp = new MemoryStream();
       pdfTemplate = new PdfReader(m_FormName);
   
       stamper = new PdfStamper(pdfTemplate, msTemp);
   
       // map xml values to pdf form controls (element name = control name)
       foreach (XmlElement oElem in oData.SelectNodes("/form/page" + i + "/*"))
       {
           stamper.AcroFields.SetField(oElem.Name, oElem.InnerText);
       }
   
       stamper.FormFlattening = true;
       stamper.Close();
       tempPDF = new PdfReader(msTemp.ToArray());
       ((PdfCopy)pCopy).AddPage(pCopy.GetImportedPage(tempPDF, i));
       pCopy.FreeReader(tempPDF);
   }
   
   doc.Close();
   
   return msOutput;
   }
   

3. Save the File or post the file to the response of your ASP.Net page