python之如何计算两个日期相差天数days

电玩女神 2021-09-30 00:04 908阅读 0赞

参考：[https://jingyan.baidu.com/article/3f16e003211db12591c103a6.html][https_jingyan.baidu.com_article_3f16e003211db12591c103a6.html]

### 自己封装的一个方法【计算两个日期的差值】 ###

@classmethod
        # 把一个字符串格式的日期【2019-7-18】或【2019.7.18】转换成(2019,7,8)数字元组
        def date_str_to_number_tuple(cls, date_str):
            if "-" in date_str:
                [year, month, day] = date_str.split("-")
            elif "." in date_str:
                [year, month, day] = date_str.split(".")
            else:
                raise Fail(f"date_str日期字符串格式必须为[年-月-日]或[年.月.日]")
            return [int(year), int(month), int(day)]
    
        @classmethod
        # 计算两个日期相差多少天days
        def compute_two_date_offset_days(cls, start_date_str, end_date_str):
            start_year_month_day = cls.date_str_to_number_tuple(start_date_str)
            end_year_month_day = cls.date_str_to_number_tuple(end_date_str)
            return (datetime.date(*end_year_month_day) - datetime.date(*start_year_month_day)).days

**参考资料：官方的date源代码兼容增删改查运算【内部实现了这些特殊方法】**

class date:
        min: ClassVar[date]
        max: ClassVar[date]
        resolution: ClassVar[timedelta]
    
        def __init__(self, year: int, month: int, day: int) -> None: ...
    
        @classmethod
        def fromtimestamp(cls, t: float) -> date: ...
        @classmethod
        def today(cls) -> date: ...
        @classmethod
        def fromordinal(cls, n: int) -> date: ...
        if sys.version_info >= (3, 7):
            @classmethod
            def fromisoformat(cls, date_string: str) -> date: ...
    
        @property
        def year(self) -> int: ...
        @property
        def month(self) -> int: ...
        @property
        def day(self) -> int: ...
    
        def ctime(self) -> str: ...
        def strftime(self, fmt: _Text) -> str: ...
        if sys.version_info >= (3,):
            def __format__(self, fmt: str) -> str: ...
        else:
            def __format__(self, fmt: AnyStr) -> AnyStr: ...
        def isoformat(self) -> str: ...
        def timetuple(self) -> struct_time: ...
        def toordinal(self) -> int: ...
        def replace(self, year: int = ..., month: int = ..., day: int = ...) -> date: ...
        def __le__(self, other: date) -> bool: ...
        def __lt__(self, other: date) -> bool: ...
        def __ge__(self, other: date) -> bool: ...
        def __gt__(self, other: date) -> bool: ...
        def __add__(self, other: timedelta) -> date: ...
        @overload
        def __sub__(self, other: timedelta) -> date: ...
        @overload
        def __sub__(self, other: date) -> timedelta: ...
        def __hash__(self) -> int: ...
        def weekday(self) -> int: ...
        def isoweekday(self) -> int: ...
        def isocalendar(self) -> Tuple[int, int, int]: ...

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