serialize method

@override String serialize()

Implementation

@override
String serialize() {
  final buffer = StringBuffer();
  buffer.write('BEGIN:ATTACHMENT\n');
  if (uri != null) buffer.write('ATTACH;FMTTYPE=$mimeType:$uri\n');
  if (binaryData != null) buffer.write('ATTACH;ENCODING=BASE64:$binaryData\n');
  buffer.write('END:ATTACHMENT');
  return buffer.toString();
}