Python对时间的处理

2017-12-07

所需模块

1 2	import time import datetime

datetime -> string

def datetime_to_string(dt, format=None):
    if format is None:
        format = "%Y-%m-%d %H:%M:%S"
    return dt.strftime(format)

1
2
3

In [3]: now = datetime.datetime.now()
In [4]: datetime_to_string(now)
Out[4]: '2017-09-20 14:54:41'

datetime -> timestamp

1
2
3


def datetime_to_timestamp(dt):
    return time.mktime(dt.timetuple())

1
2
3

In [20]: now = datetime.datetime.now()
In [21]: datetime_to_timestamp(now)
Out[21]: 1505890893.0

string -> datetime


def string_to_datetime(time_str, format=None):
    if format is None:
        format = "%Y-%m-%d %H:%M:%S"
    return datetime.datetime.strptime(time_str, format)

1
2
3

In [6]: time_str = "2017-09-20 14:54:41"
In [7]: string_to_datetime(time_str)
Out[7]: datetime.datetime(2017, 9, 20, 14, 54, 41)

string -> timestamp


def string_to_timestamp(time_str, format=None):
    if format is None:
        format = "%Y-%m-%d %H:%M:%S"
    dt = datetime.datetime.strptime(time_str, format)
    return time.mktime(dt.timetuple())

1
2
3

In [13]: time_str = "2017-09-20 14:54:41"
In [14]: string_to_timestamp(time_str)
Out[14]: 1505890481.0

timestamp -> string


def timestamp_to_string(stamp, format=None):
    if format is None:
        format = "%Y-%m-%d %H:%M:%S"
    return time.strftime(format, time.localtime(stamp))

1
2
3

In [17]: now = time.time()
In [18]: timestamp_to_string(now)
Out[18]: '2017-09-20 15:00:46'

timestamp -> datetime

1
2
3


def timestamp_to_datetime(stamp):
    return datetime.datetime.fromtimestamp(stamp)

1
2
3

In [24]: now = time.time()
In [25]: timestamp_to_datetime(now)
Out[25]: datetime.datetime(2017, 9, 20, 15, 6, 22, 861949)