2-datetime 模块
- 2020 年 1 月 2 日
- 筆記
datetime
时间转字符串
在我们的使用中，我们常常需要将时间转换为字符串，用来作为文件的名字或者用于加密字符的输出等等。例子：
from datetime import datetime datetime.strftime(datetime.now(),"%Y-%m-%d %H:%M:%S")
记忆方式也很简单，str from time
字符转时间
有时候我们需要将一个字符给转换为时间对象
from datetime import datetime >>> datetime.strptime('2018-09-09',"%Y-%m-%d") datetime.datetime(2018, 9, 9, 0, 0)
时间戳的转换
import time from datetime import datetime stamp = time.time() datetime.fromtimestamp(stamp)
timedelta
import datetime print('microseconds:', datetime.timedelta(microseconds=1)) print('milliseconds:', datetime.timedelta(milliseconds=1)) print('seconds :', datetime.timedelta(seconds=1)) print('minutes :', datetime.timedelta(minutes=1)) print('hours :', datetime.timedelta(hours=1)) print('days :', datetime.timedelta(days=1)) print('weeks :', datetime.timedelta(weeks=1))
加 就是 延后几秒; 减 就是提前几秒
转换格式
|
Symbol |
Meaning |
Example |
|---|---|---|
|
%a |
Abbreviated weekday name |
'Wed' |
|
%A |
Full weekday name |
'Wednesday' |
|
%w |
Weekday number: 0 (Sunday) through 6 (Saturday) |
'3' |
|
%d |
Day of the month (zero padded) |
'13' |
|
%b |
Abbreviated month name |
'Jan' |
|
%B |
Full month name |
'January' |
|
%m |
Month of the year |
'01' |
|
%y |
Year without century |
'18' |
|
%Y |
Year with century |
'2018' |
|
%H |
Hour from 24-hour clock |
'17' |
|
%I |
Hour from 12-hour clock |
'05' |
|
%p |
AM/PM |
'PM' |
|
%M |
Minutes |
'00' |
|
%S |
Seconds |
'00' |
|
%f |
Microseconds |
'000000' |
|
%z |
UTC offset for time zone–aware objects |
'-0500' |
|
%Z |
Time zone name |
'EST' |
|
%j |
Day of the year |
'013' |
|
%W |
Week of the year |
'02' |
|
%c |
Date and time representation for the current locale |
'Wed Jan 13 17:00:00 2016' |
|
%x |
Date representation for the current locale |
'01/13/16' |
|
%X |
Time representation for the current locale |
'17:00:00' |
|
%% |
A literal % character |
'%' |
tips
工作中经常需要用到美国时间，做一个记录。 utc晚了8个小时，所以要减去即是美国时间
datetime.strftime(datetime.utcnow()-timedelta(hours=8),'%Y-%m-%d %H:%M:%S')
参考
《The Python3 Standard Library By Example》
