如何在 Python 中将日期时间对象转换为自纪元（unix 时间）以来的毫秒数？

Question

I have a Python datetime object that I want to convert to unix time, or seconds/milliseconds since the 1970 epoch.

How do I do this?

Answer 1

It appears to me that the simplest way to do this is

import datetime

epoch = datetime.datetime.utcfromtimestamp(0)

def unix_time_millis(dt):
    return (dt - epoch).total_seconds() * 1000.0

Answer 2

In Python 3.3, added new method timestamp :

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

Your question stated that you needed milliseconds, which you can get like this:

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

If you use timestamp on a naive datetime object, then it assumed that it is in the local timezone. Use timezone-aware datetime objects if this is not what you intend to happen.

Answer 3

>>> import datetime
>>> # replace datetime.datetime.now() with your datetime object
>>> int(datetime.datetime.now().strftime("%s")) * 1000 
1312908481000

Or the help of the time module (and without date formatting):

>>> import datetime, time
>>> # replace datetime.datetime.now() with your datetime object
>>> time.mktime(datetime.datetime.now().timetuple()) * 1000
1312908681000.0

Answered with help from: http://pleac.sourceforge.net/pleac_python/datesandtimes.html

Documentation:

• time.mktime
• datetime.timetuple

Answer 4

You can use Delorean to travel in space and time!

import datetime
import delorean
dt = datetime.datetime.utcnow()
delorean.Delorean(dt, timezone="UTC").epoch

http://delorean.readthedocs.org/en/latest/quickstart.html

Answer 5

This is how I do it:

from datetime import datetime
from time import mktime

dt = datetime.now()
sec_since_epoch = mktime(dt.timetuple()) + dt.microsecond/1000000.0

millis_since_epoch = sec_since_epoch * 1000

Answer 6

Recommendedations from the Python 2.7 docs for the time module

Answer 7

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))

Answer 8

Here's another form of a solution with normalization of your time object:

def to_unix_time(timestamp):
    epoch = datetime.datetime.utcfromtimestamp(0) # start of epoch time
    my_time = datetime.datetime.strptime(timestamp, "%Y/%m/%d %H:%M:%S.%f") # plugin your time object
    delta = my_time - epoch
    return delta.total_seconds() * 1000.0

Answer 9

>>> 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

Answer 10

A bit of pandas code:

import pandas

def to_millis(dt):
    return int(pandas.to_datetime(dt).value / 1000000)

Answer 11

import time
seconds_since_epoch = time.mktime(your_datetime.timetuple()) * 1000

Answer 12

Here is a function I made based on the answer above

def getDateToEpoch(myDateTime):
    res = (datetime.datetime(myDateTime.year,myDateTime.month,myDateTime.day,myDateTime.hour,myDateTime.minute,myDateTime.second) - datetime.datetime(1970,1,1)).total_seconds()
    return res

You can wrap the returned value like this : str(int(res)) To return it without a decimal value to be used as string or just int (without the str)

Answer 13

A lot of these answers don't work for python 2 or don't preserve the milliseconds from the datetime. This works for me

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

Answer 14

This other solution for covert datetime to unixtimestampmillis.

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;
    }