在 datetime 对象中添加或更改时间

Question

I have multiple datetime objects, for example:

>>a
datetime.datetime(2009, 11, 1, 0, 0)

I want to keep date unchanged and alter time to zeros (three digits in time):

>>b
datetime.datetime(2009, 11, 1, 0, 0, 0)

Probably simple but i can't figure it out

EDIT: For some reason a zero for seconds doesnt work. It does not matter, it works with a 1:

>>a
datetime.datetime(2009, 11, 1, 0, 0)
>>b = datetime.datetime.combine(a.date(), datetime.time(0,0,0))
>>b
datetime.datetime(2009, 11, 1, 0, 0)
>>b = datetime.datetime.combine(a.date(), datetime.time(0,0,1))
>>b
datetime.datetime(2009, 11, 1, 0, 0, 1)

Answer 1

这有点繁琐，但您可以使用combine ：

b = datetime.datetime.combine(a.date(), datetime.time(0,0,0))

Answer 2

import datetime
date_with_zeros = datetime.datetime(2009, 11, 1, 1, 0, 0).replace(hour=0, minute=0, second=0)

Just use replace.

Answer 3

datetime.datetime(2009, 11, 1, 0, 0) and datetime.datetime(2009, 11, 1, 0, 0, 0) create the same datetime objects. See https://docs.python.org/2/library/datetime.html#datetime.datetime for details.

If you have non-zero hours, minutes or seconds you can use replace to make them zero:

dt = datetime.datetime(2009, 11, 1, 3, 15, 49)
dt.replace(hour=0, minute=0, second=0)