RadPdfProcessing currently supports interactive forms whose data is defined directly in the document. Add support for interactive forms based on the Adobe XML Forms Architecture (XFA). The entry is defined inside the interactive forms dictionary and refers to an XML stream containing the information of the form. More information is available on page 722 from Pdf Reference, version 1.7.
Updates:
RadPdfProcessing currently supports interactive forms whose data is defined directly in the document. To preserve them when importing and exporting documents, add support for import-export interactive forms based on the Adobe XML Forms Architecture (XFA).
From PDF 2.0 the XFA forms are depreciated.