• DateTime
表示一个指定的时间点，包括年月日时分秒

• TimeOfDay
表示一天中的一个时间点，可以区分上午，下午，12小时制，24小时制等

获取当前时间

final now = DateTime.now();

final year = now.year;
final month = now.month;
final day = now.day;

final week = now.weekday;

转时间戳

final now = DateTime.now();
String timestamp = now.millisecondsSinceEpoch.toString();

时间运算

• 前2天

final now = DateTime.now();
final before = now.subtract(Duration(days: 2));

• 后2天

final now = DateTime.now();
final after = now.add(Duration(days: 2));

• 两个时间点相隔的时间数

final now = DateTime.now();
final after = now.add(Duration(days: 2));
final diff = after.difference(now).inHours; // 相隔的小时数，也可以是分钟数，秒数

上午还是下午

final timeOfDay = TimeOfDay.now();
final amOrPm = timeOfDay.period;

enum DayPeriod {
  /// Ante meridiem (before noon).
  am,

  /// Post meridiem (after noon).
  pm,
}

12/24小时制

• 24小时

final hour24 = timeOfDay.hour;

• 12小时

final hour12 = timeOfDay.hourOfPeriod;

final timeStr = timeOfDay.format(context); // 11:49 PM