toICalString method
Implementation
String toICalString() {
final buffer = StringBuffer();
buffer.write('EXDATE');
if (timeZone.isUtc) {
buffer.write('Z');
buffer.write(':');
buffer.write(DateFormat('yyyyMMdd\'T\'HHmmss').format(date));
} else {
buffer.write(';TZID=${timeZone.tzId}');
buffer.write(':');
buffer.write(DateFormat('yyyyMMdd\'T\'HHmmss').format(date));
}
return buffer.toString();
}