如何将GMT时间转换为本地时间

Question

我是python新手，我需要将air_time变量转换为本地机器时间，或将current_time变量转换为GMT，然后在此脚本中从其他变量中减去一个，但不知道如何执行

from datetime import datetime

air_time_GMT = '2020-08-05 13:30:00'
air_time = datetime.strptime(air_time_GMT, '%Y-%m-%d %H:%M:%S')
current_time = datetime.now()

time_remaining = air_time - current_time

print(time_remaining)

Answer 1

下面是一种方法，您可以在评论中进行一些解释：

from datetime import datetime, timezone

air_time_GMT = '2020-08-05 13:30:00'

# Python will assume your input is local time if you don't specify a time zone:
air_time = datetime.strptime(air_time_GMT, '%Y-%m-%d %H:%M:%S')
# ...so let's do this:
air_time = air_time.replace(tzinfo=timezone.utc) # using UTC since it's GMT
       
# again, if you don't supply a time zone, you will get a datetime object that
# refers to local time but has no time zone information:
current_time = datetime.now()

# if you want to compare this to a datetime object that HAS time zone information,
# you need to set it here as well. You can set local time zone via
current_time = current_time.astimezone()

print(current_time)
print(air_time-current_time)
>>> 2020-08-05 14:11:45.209587+02:00 # note that my machine is on UTC+2 / CEST
>>> 1:18:14.790413

我想你应该注意两件事

• 首先，Python默认假定datetime对象属于本地时间（OS时区设置），如果它是原始的（没有时区信息）
• 其次，您不能将naive日期时间对象（未定义时区/UTC偏移量）与aware日期时间对象（给定时区信息）进行比较

[datetime module docs]