Native FDF and XFDF form data
HPDFHeadlessFormData provides bounded FDF and XFDF codecs, and THPDFHeadlessDocument ties their Unicode field model to actual AcroForm values and appearances
ExportFormData returns canonical form-data bytes; ImportFormDataToFile applies the whole decoded model to an independently prepared graph and atomically publishes an incremental PDF
Text, checkboxes, radio groups, single and multiple choices and nested Unicode field names are supported; signature and pushbutton fields export name-only entries
ImportRichFormDataToFile imports real FDF RV and XFDF value-richtext, preserves ordered mixed Unicode content and regenerates actual regular, bold, italic and bold-italic appearances through the bounded XHTML style profile
FDF input supports direct and indirect field dictionaries, indirect reference chains, nested Kids, scalar PDF text strings, escaped PDF name values and text arrays; output writes hierarchical FDF 1.2 with UTF-16BE strings
XFDF input supports the standard namespace, qualified namespace prefixes, nested fields, UTF-8, BOM-marked UTF-16, comments, CDATA, predefined entities and numeric character references; output is canonical UTF-8 XML
For a choice field without an empty export option, a single empty XFDF value clears the selection; when an empty export option exists, the same value picks that option
AES-256 R5 and R6 authentication, original encryption dictionaries, identifiers and permissions are preserved; an authenticated source key is borrowed solely for the private matching revision graph
Actual DocMDP P2 and P3 allow permitted appearance updates whilst P1, FieldMDP locks and read-only flags stay enforced; existing CMS signatures keep their exact signed revisions
Named-family form import selects supplied family programs for actual FDF RV and XFDF value-richtext; arbitrary CSS layout, per-glyph font fallback, embedded FDF files, actions and incremental FDF trailers are still active capabilities
Native annotation XFDF exchange adds an independent bounded append profile for eighteen mapped annotation types, popup/reply relationships and binary attachments
Limits and cancellation · Field model · Decode · Encode · Form-data exceptions
Internal style sheets apply bounded selectors, importance, specificity and source order to actual imported rich values and saved appearances; repeated equivalent imports and failed publication retain the existing transaction guarantees
Binary annotation graphs
Native annotation FDF exchange preserves supplied annotation dictionaries, appearance resources, shared indirect objects and context-sensitive local GoTo targets through a bounded PDF object graph
Annotation-only FDF operations use separate THPDFFDFOptions and reject nonempty Fields or embedded document Differences; use the field-data APIs above to apply field values
Modern Windows loaded-document interchange can combine selected fields, annotation graphs and workflow status through ExportLoadedInterchangeToFDF and ImportLoadedInterchangeFromFDF
Explicit annotation removal
Page-and-name annotation removal is a separate operation; omitting an annotation from imported FDF or XFDF does not delete it
Widget field-tree deletion and secure erasure require separate operations; incremental removal retains previous PDF bytes