lastMonthStart property

DateTime lastMonthStart

上个月起始时刻，上月1日0时

Implementation

static DateTime get lastMonthStart {
  final now = DateTime.now();
  var year = now.year;
  var month = now.month;
  if (month == 1) {
    // 如果当前是1月份，上月为去年12月份
    year = year - 1;
    month = 12;
  } else {
    // 否则上月等于本月-1
    month = month - 1;
  }

  return DateTime(year, month, 1, 0, 0, 0);
}