python 将 1970 年之前的日期的文件时间转换为日期时间

python convert filetime to datetime for dates before 1970

我需要将文件时间转换为日期时间。我正在使用此代码 filetime.py, from here as mentioned in this thread Datetime to filetime (Python)

在代码中

EPOCH_AS_FILETIME = 116444736000000000  # January 1, 1970 as MS file time
HUNDREDS_OF_NANOSECONDS = 10000000

def filetime_to_dt(ft):
    """Converts a Microsoft filetime number to a Python datetime. The new datetime object is time zone-naive but is equivalent to tzinfo=utc.

    >>> filetime_to_dt(116444736000000000)
    datetime.datetime(1970, 1, 1, 0, 0)
    """
    # Get seconds and remainder in terms of Unix epoch
    (s, ns100) = divmod(ft - EPOCH_AS_FILETIME, HUNDREDS_OF_NANOSECONDS)
    # Convert to datetime object
    dt = datetime.utcfromtimestamp(s)
    # Add remainder in as microseconds. Python 3.2 requires an integer
    dt = dt.replace(microsecond=(ns100 // 10))
    return dt

datetime.utcfromtimestamp 在 windows 系统上不取负值,所以我无法转换 1970 年 1 月 1 日之前的文件时间。但是我可以使用 Mac 转换 1970 年之前的日期完全相同的代码(原因 here)。 windows 有任何解决方法吗?

According to docs,你必须使用:

dt = datetime.fromtimestamp(s, datetime.timezone.utc)

而不是:

dt = datetime.utcfromtimestamp(s)

通过向参考日期添加 timedelta,您可以使用任何您喜欢的日期公式。 timedelta可正可负。

def filetime_to_dt(ft):
    us = (ft - EPOCH_AS_FILETIME) // 10
    return datetime(1970, 1, 1) + timedelta(microseconds = us)

首先您需要将其转换为可识别的文件时间格式,如下所示:

>>> dwLowDateTime = 0x0F7297A80
>>> dwHighDateTime = 0x1C3F10F << 32
>>> ft = (dwLowDateTime & 0xFFFFFFFF) | dwHighDateTime
127210265370000000

然后使用这个脚本,它将文件时间转换为日期时间,反之亦然https://gist.github.com/Mostafa-Hamdy-Elgiar/9714475f1b3bc224ea063af81566d873

>>> filetime_to_dt(ft)
2004-02-12 02:28:57

在时间范围之间使用 timedeltas 到 add/subtract/divide:

FILE_TIME_EPOCH = datetime.datetime(1601, 1, 1)
FILE_TIME_MICROSECOND = 10 # FILETIME counts 100 nanoseconds intervals = 0.1 microseconds, so 10 of those are 1 microsecond

def convert_from_file_time(file_time):
    microseconds_since_file_time_epoch = file_time // FILE_TIME_MICROSECOND
    return FILE_TIME_EPOCH + datetime.timedelta(microseconds=microseconds_since_file_time_epoch)

另一面是:

def convert_to_file_time(date_time):
    microseconds_since_file_time_epoch = (date_time - FILE_TIME_EPOCH) // datetime.timedelta(microseconds=1)
    return microseconds_since_file_time_epoch * FILE_TIME_MICROSECOND