Python中的日期/时间处理 by aafeng

hive-105017 · @aafeng · Jun 1 '20

$10.90

Python中的日期/时间处理

在写代码的时候有很多场合需要处理日期和时间，比如：在日志中需要记录当前时间，在处理订单的时候需要处理用户下单的时间，在Hive上的各种点赞机器人需要知道新帖子的创建时间，以及帖子的“年龄“。。。在Python中提供了非常强大的日期/时间处理模块：time和datetime，这些模块中又有很多有用的函数。下面把我经常使用的函数做一总结，欢迎大家指正。
![](https://images.hive.blog/1280x0/https://images.hive.blog/DQmPSoZ1PRToUoJwd9awj9XaGKf9pYnKDsRkkVjzUEgtc9K/image.png)

## time模块

time模块提供了和时间相关的一些类及函数。

### 时间偏移量表示法

在Python交互式窗口中输入time.time()，其输出为一个数字：

![image](https://user-images.githubusercontent.com/63479035/83278821-14a55000-a1cc-11ea-98d5-1dd0aadb4248.png)

这个数字代表了从1970年1月1日00:00:00至今的秒偏移量。

将其转换为字符串格式：

![image](https://user-images.githubusercontent.com/63479035/83278933-41596780-a1cc-11ea-8927-c20cc9f800fc.png)

### 元组表示法

还有一种时间的表示法：使用包含9个整数的元组分别表示年，月，日，时，分，秒等：

![image](https://user-images.githubusercontent.com/63479035/83278369-6a2d2d00-a1cb-11ea-855c-b0eb3513c761.png)

可以把这个元组转换为第一种表示法：

![image](https://user-images.githubusercontent.com/63479035/83278291-4538ba00-a1cb-11ea-9f1c-1cf71f0b6964.png)

### 格式化字符串表示法

这个时间还可以表示为我们熟悉的格式：

![image](https://user-images.githubusercontent.com/63479035/83278215-233f3780-a1cb-11ea-8f22-4eb83349238a.png)    

### 时间的加减法

比如，计算一个小时之后的时间：

![image](https://user-images.githubusercontent.com/63479035/83278106-f723b680-a1ca-11ea-8fd4-c2e2b5aea672.png)

## datetime模块

从 datetime 模块中，依次导入date，datetime，timedelta。

    from datetime import date, datetime, timedelta

### 获取日期

获取当前日期：

![image](https://user-images.githubusercontent.com/63479035/83279289-cfcde900-a1cc-11ea-8261-3ec8beabeaef.png)

### 日期时间和字符串转换

将日期转换为字符串；

![image](https://user-images.githubusercontent.com/63479035/83304054-0d933780-a1f6-11ea-80ee-cf50b1c46643.png)

将日期时间字符串转换为日期时间(datetime)类型：


![image](https://user-images.githubusercontent.com/63479035/83304510-e4bf7200-a1f6-11ea-8c1d-00a087064f0e.png)

### 计算时间差

![image](https://user-images.githubusercontent.com/63479035/83305023-d756b780-a1f7-11ea-8a13-af5aabfe4060.png)

获取明天和昨天的时间：

![image](https://user-images.githubusercontent.com/63479035/83308608-0c1a3d00-a1ff-11ea-8f64-d1fee939508c.png)

得到Hive文章的发布时间后，计算从文章发布时间到现在时间的秒数：

![image](https://user-images.githubusercontent.com/63479035/83308289-68c92800-a1fe-11ea-8f6d-33e40dc305e5.png)

👍 sweetsssj, abit, hive.curation, max.curation, btscn, aafeng, victory622, created, livingfree, susanli3769, spt-skillup, bala41288, lebin, digital.mine, bring, gitplait, accelerator, exyle, freddio, ezzy, gerber, mapxv, map10k, nealmcspadden, aleister, sabari18, emrebeyler, tykee, someguy123, muntaharaceh, xiaoshancun, dancingapple, dlike, freddio.sport, ffcrossculture, mangoanddaddy, steem.leo, bestboom, asteroids, tagalong, leo.voter, freedomteam2019, maiyude, followjohngalt, shihabieee, dune69, mice-k, maxuvd, caladan, felander, drew0, cadawg, fishbb, aafeng.test, steemcityrewards, citrus-soap, deathwing, ribary, cmdd, gerbo

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properties (23)vote details (60)

voter	rshares	pct
abit	7,006,518,571,081	30%
gerber	26,806,335,033	0.39%
ezzy	30,177,285,724	0.39%
livingfree	143,693,068,238	1%
exyle	37,197,533,928	0.39%
ffcrossculture	3,061,752,250	1%
sweetsssj	13,547,047,142,561	33%
someguy123	5,493,599,198	0.39%
created	167,405,535,814	1%
bring	65,719,405,831	100%
dune69	1,439,259,449	0.39%
aleister	10,041,625,757	10%
susanli3769	140,617,010,104	100%
tykee	6,814,831,410	50%
mangoanddaddy	3,039,537,180	80%
aafeng	217,795,320,679	100%
shihabieee	1,439,648,599	16.5%
felander	1,158,923,401	0.39%
accelerator	39,461,270,363	4%
deathwing	136,437,780	0.39%
dancingapple	4,729,792,282	20%
xiaoshancun	4,875,417,761	100%
victory622	185,349,430,071	100%
caladan	1,180,013,231	0.39%
emrebeyler	7,924,613,964	0.35%
lebin	92,817,221,510	50%
nealmcspadden	10,198,376,384	0.39%
maiyude	1,732,395,836	50%
bala41288	108,091,413,711	50%
cadawg	664,075,570	0.27%
fishbb	583,015,361	25%
bestboom	2,643,151,342	0.39%
freddio	33,273,994,077	15%
digital.mine	70,683,674,370	0.3%
sabari18	7,956,584,283	30%
dlike	4,607,407,671	0.39%
followjohngalt	1,705,035,595	0.39%
muntaharaceh	5,297,726,257	100%
tagalong	2,529,126,306	100%
aafeng.test	551,497,359	100%
map10k	10,252,480,523	12%
steem.leo	2,756,561,110	0.38%
leo.voter	2,466,607,604	0.07%
freddio.sport	4,591,216,086	15%
asteroids	2,558,798,552	0.39%
mapxv	11,509,103,610	14%
citrus-soap	154,269,765	0.39%
spt-skillup	137,859,020,353	10%
maxuvd	1,340,744,597	0.39%
btscn	232,868,080,039	50%
freedomteam2019	2,144,087,551	30%
gerbo	0	0.39%
max.curation	343,670,958,278	64.05%
ribary	75,308,333	0.19%
cmdd	12,517,505	100%
mice-k	1,425,451,069	0.39%
drew0	788,538,384	5%
steemcityrewards	493,658,212	0.39%
gitplait	55,394,025,946	100%
hive.curation	374,464,017,138	14.41%