cal_days_in_month的month参数可能会小于等于0导致报错 cal_days_in_month(): invalid date. 重现如下 date("Y-m-d H:i:s", Date::unixtime("month", -1, 'start', 2021, 1, 1, 0, 0, 0)); 更新后测试方法 $offset = [-240,-24,-23,-22,-21,-20,-19,-18,-17,-16,-15,-14,-...