给定一个日期时间。在Python中，是否有一种标准的方法来添加一个整数秒数，例如11:34:59 + 3 = 11:35:02 ?
这些显而易见的想法并不奏效:
>>> datetime.time(11, 34, 59) + 3
TypeError: unsupported operand type(s) for +: 'datetime.time' and 'int'
>>> datetime.time(11, 34, 59) + datetime.timedelta(0, 3)
TypeError: unsupported operand type(s) for +: 'datetime.time' and 'datetime.timedelta'
>>> datetime.time(11, 34, 59) + datetime.time(0, 0, 3)
TypeError: unsupported operand type(s) for +: 'datetime.time' and 'datetime.time'
最后我写出了这样的函数:
def add_secs_to_time(timeval, secs_to_add):
secs = timeval.hour * 3600 + timeval.minute * 60 + timeval.second
secs += secs_to_add
return datetime.time(secs // 3600, (secs % 3600) // 60, secs % 60)
我不禁想，我错过了一个更简单的方法来做到这一点。
相关的
Python time + timedelta等价
老问题了，但我想我应该加入一个处理时区的函数。关键部分是传递datetime。Time对象的tzinfo属性合并，然后在生成的虚拟datetime上使用timez()而不是Time()。这个答案在一定程度上受到了这里其他答案的启发。
def add_timedelta_to_time(t, td):
"""Add a timedelta object to a time object using a dummy datetime.
:param t: datetime.time object.
:param td: datetime.timedelta object.
:returns: datetime.time object, representing the result of t + td.
NOTE: Using a gigantic td may result in an overflow. You've been
warned.
"""
# Create a dummy date object.
dummy_date = date(year=100, month=1, day=1)
# Combine the dummy date with the given time.
dummy_datetime = datetime.combine(date=dummy_date, time=t, tzinfo=t.tzinfo)
# Add the timedelta to the dummy datetime.
new_datetime = dummy_datetime + td
# Return the resulting time, including timezone information.
return new_datetime.timetz()
下面是一个非常简单的测试用例类(使用内置的unittest):
import unittest
from datetime import datetime, timezone, timedelta, time
class AddTimedeltaToTimeTestCase(unittest.TestCase):
"""Test add_timedelta_to_time."""
def test_wraps(self):
t = time(hour=23, minute=59)
td = timedelta(minutes=2)
t_expected = time(hour=0, minute=1)
t_actual = add_timedelta_to_time(t=t, td=td)
self.assertEqual(t_expected, t_actual)
def test_tz(self):
t = time(hour=4, minute=16, tzinfo=timezone.utc)
td = timedelta(hours=10, minutes=4)
t_expected = time(hour=14, minute=20, tzinfo=timezone.utc)
t_actual = add_timedelta_to_time(t=t, td=td)
self.assertEqual(t_expected, t_actual)
if __name__ == '__main__':
unittest.main()
您可以使用完整的datetime变量和timedelta，并通过提供一个虚拟日期，然后使用time来获得时间值。
例如:
import datetime
a = datetime.datetime(100,1,1,11,34,59)
b = a + datetime.timedelta(0,3) # days, seconds, then other fields.
print(a.time())
print(b.time())
结果是两个值，间隔三秒:
11:34:59
11:35:02
你也可以选择可读性更强的
b = a + datetime.timedelta(seconds=3)
如果你愿意的话。
如果你在寻找一个可以做到这一点的函数，你可以使用下面的addSecs:
import datetime
def addSecs(tm, secs):
fulldate = datetime.datetime(100, 1, 1, tm.hour, tm.minute, tm.second)
fulldate = fulldate + datetime.timedelta(seconds=secs)
return fulldate.time()
a = datetime.datetime.now().time()
b = addSecs(a, 300)
print(a)
print(b)
这个输出:
09:11:55.775695
09:16:55
