Is it possible to modify PDF Form Field Names?

Question

Here's the situation. I have a PDF with automatically generated pdf form field names. The problem is that these names are not very user friendly. They look something like : topmostSubform[0].Page1[0].Website_Address[0]

I want to be able to change them so that they are something like WebsiteAddress. I have access to ABCPDF and I have experience with iTextSharp, but I have tried using these API's to do this (access form fields and try to rename), but it does not seem as if it is possible.

Does anybody have any experience trying to do this via an API of some sort (preferably open source). Code is .Net also.

Answer 1

The good news: you can change field names in iTextSharp.

You can't actually edit a PDF though. You'd read in an existing PDF, update your field names in memory and then write out your revised PDF. To change a field name call the AcroFields.RenameField method.

Here's a snippet:

PdfReader reader = new PdfReader(PDF_PATH);
using (FileStream fs = new FileStream("Test Out.pdf", FileMode.Create)) {
    PdfStamper stamper = new PdfStamper(reader, fs);
    AcroFields fields = stamper.AcroFields;
    fields.RenameField("oldFieldName", "newFieldName");
    stamper.Close();
}

Now the bad news: there appear to be limitations in the characters you can use in the renamed fields.

I tested the snippet above with your example field name and it didn't work. Remove the periods though and it does work. I'm not sure if there's a workaround but this may be a problem for you,