toJson method
Implementation
Map<String, Object?> toJson() => <String, Object?>{
"title": title,
"author": author,
"subject": subject,
"keywords": keywords,
"creator": creator,
"producer": producer,
"creationDate": creationDate?.toIso8601String(),
"modificationDate": modificationDate?.toIso8601String(),
"language": language,
"publisher": publisher,
"identifier": identifier,
"series": series,
"seriesIndex": seriesIndex,
"pageCount": pageCount,
"version": version,
"tagged": tagged,
"linearized": linearized,
"encrypted": encrypted,
"custom": custom,
};