THPDFHeadlessDocument.ImportRichFormDataWithFamiliesToFile
function ImportRichFormDataWithFamiliesToFile(const FileName: string;
const Bytes: SysUtils.TBytes; Format: THPDFHeadlessFormDataFormat;
const Families: THPDFHeadlessRichTextFontFamilies;
const AppearanceOptions: THPDFHeadlessTextAppearanceOptions;
const Options: THPDFHeadlessFormDataOptions): Integer;
Import real FDF or XFDF fields into an independent output, choosing named families for XHTML rich values; the first family supplies the scalar text, button and choice fonts
The return value counts the changed fields; canonical named rich values take part in the existing semantic no-op comparison, which does not promise byte-identical reserialisation
The loaded source graph stays untouched; the existing transaction, destination alias, field policy, security, authenticated signature, budget and cancellation rules all apply