很多答案在python2中不起作用，或者没有从datetime中保存毫秒。这对我很有用

def datetime_to_ms_epoch(dt):
    microseconds = time.mktime(dt.timetuple()) * 1000000 + dt.microsecond
    return int(round(microseconds / float(1000)))

>>> import datetime
>>> import time
>>> import calendar

>>> #your datetime object
>>> now = datetime.datetime.now()
>>> now
datetime.datetime(2013, 3, 19, 13, 0, 9, 351812)

>>> #use datetime module's timetuple method to get a `time.struct_time` object.[1]
>>> tt = datetime.datetime.timetuple(now)
>>> tt
time.struct_time(tm_year=2013, tm_mon=3, tm_mday=19, tm_hour=13, tm_min=0, tm_sec=9,     tm_wday=1, tm_yday=78, tm_isdst=-1)

>>> #If your datetime object is in utc you do this way. [2](see the first table on docs)
>>> sec_epoch_utc = calendar.timegm(tt) * 1000
>>> sec_epoch_utc
1363698009

>>> #If your datetime object is in local timeformat you do this way
>>> sec_epoch_loc = time.mktime(tt) * 1000
>>> sec_epoch_loc
1363678209.0

[1] http://docs.python.org/2/library/datetime.html#datetime.date.timetuple

[2] http://docs.python.org/2/library/time.html

Python 2.7文档对time模块的建议

这是将datetime转换为unixtimestampmillis的另一个解决方案。

private static readonly DateTime UnixEpoch = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);

    public static long GetCurrentUnixTimestampMillis()
    {
        DateTime localDateTime, univDateTime;
        localDateTime = DateTime.Now;          
        univDateTime = localDateTime.ToUniversalTime();
        return (long)(univDateTime - UnixEpoch).TotalMilliseconds;
    } 

from datetime import datetime
from calendar import timegm

# Note: if you pass in a naive dttm object it's assumed to already be in UTC
def unix_time(dttm=None):
    if dttm is None:
       dttm = datetime.utcnow()

    return timegm(dttm.utctimetuple())

print "Unix time now: %d" % unix_time()
print "Unix timestamp from an existing dttm: %d" % unix_time(datetime(2014, 12, 30, 12, 0))

在Python 3.3中，添加了新的方法timestamp:

import datetime
seconds_since_epoch = datetime.datetime.now().timestamp()

你的问题说你需要毫秒，你可以得到这样的毫秒:

milliseconds_since_epoch = datetime.datetime.now().timestamp() * 1000

如果在naive datetime对象上使用时间戳，则假定该对象位于本地时区。如果您不希望发生这种情况，请使用时区感知的datetime对象。