toJson method
Implementation
Map<String, dynamic> toJson() => {
"valueCoding": valueCoding?.toJson(),
"valueString": valueString,
"valueDate":
"${valueDate?.year.toString().padLeft(4, '0')}-${valueDate?.month.toString().padLeft(2, '0')}-${valueDate?.day.toString().padLeft(2, '0')}",
};