又肝了3天，整理了80个Python DateTime 例子，必须收藏！（下）-阿里云开发者社区

42 从工作日值中获取工作日名称

import calendar
print(calendar.day_name[0])
print(calendar.day_name[1])
print(calendar.day_name[2])
print(calendar.day_name[3])
print(calendar.day_name[4])
print(calendar.day_name[5])
print(calendar.day_name[6])

Output:

Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
Sunday

43 将 N 小时数添加到当前日期时间

from datetime import datetime, timedelta
d = datetime.today() + timedelta(hours=18)
print(d)

Output:

2021-05-16 07:36:08.189948

44 从当前日期获取年、月、日、小时、分钟

import datetime
now = datetime.datetime.now()
print(now.year, now.month, now.day, now.hour, now.minute, now.second)

Output:

2021 5 15 14 27 33

45 获取特定月份和年份的最后一个星期日

import calendar
month = calendar.monthcalendar(2021, 2)
last_sunday = max(month[-1][calendar.SUNDAY], month[-2][calendar.SUNDAY])
print(last_sunday)

Output:

46 查找特定日期的年份中的哪一天

import pendulum
dt = pendulum.parse('2015-05-18')
print(dt.day_of_year)
dt = pendulum.parse('2019-12-01')
print(dt.day_of_year)
dt = pendulum.parse('2018-01-21')
print(dt.day_of_year)

Output:

138
21

47 查找当前日期是工作日还是周末

import datetime
weekno = datetime.datetime.today().weekday()
if weekno < 5:
    print("Weekday")
else:  # 5 Sat, 6 Sun
    print("Weekend")

Output:

Weekday

48 组合 datetime.date 和 datetime.time 对象

import datetime
d = datetime.datetime.combine(datetime.date(2020, 11, 14),
                              datetime.time(10, 23, 15))
print(d)

Output:

2020-11-14 10:23:15

49 获得每月的第 5 个星期一

import calendar
c = calendar.Calendar(firstweekday=calendar.SUNDAY)
year = 2016
month = 2
monthcal = c.monthdatescalendar(year, month)
    fifth_monday = [day for week in monthcal for day in week if
                    day.weekday() == calendar.MONDAY and day.month == month][4]
    print(fifth_monday)
except IndexError:





    
    print('No date found')

Output:

2016-02-29

50 将日期时间对象转换为日期对象

from datetime import datetime
datetime_obj = datetime(2020, 12, 15, 10, 15, 45, 321474)
print(datetime_obj)
date_obj = datetime_obj.date()
print(date_obj)

Output:

2020-12-15 10:15:45.321474
2020-12-15

51 获取没有微秒的当前日期时间

from datetime import datetime
print(datetime.now().isoformat(' ', 'seconds'))

Output:

2021-05-15 12:55:45

52 将 N 秒数添加到特定日期时间

import datetime
a = datetime.datetime(2020, 12, 31, 23, 59, 45)
b = a + datetime.timedelta(seconds=30)
print(a)
print(b)

Output:

2020-12-31 23:59:45
2021-01-01 00:00:15

53 从当前日期获取两位数的月份和日期

import datetime
dt = datetime.datetime.now()
print(dt.strftime('%m'))
print('{:02d}'.format(dt.month))
print(f'{dt.month:02d}')
print('%02d' % dt.month)
print(dt.strftime('%d'))
print('{:02d}'.format(dt.day))
print(f'{dt.day:02d}')
print('%02d' % dt.day)

Output:

05
15

54 从特定日期获取月份数据的开始和结束日期

import pendulum
dt = pendulum.datetime(2012, 9, 5)
start = dt.start_of('month')
print(start.to_datetime_string())
end = dt.end_of('month')
print(end.to_datetime_string())

Output:

2012-09-01 00:00:00
2012-09-30 23:59:59

55 以周为单位的两个日期之间的差异

from datetime import date
date1 = date(2020, 12, 23)





    
date2 = date(2021, 5, 11)
days = abs(date1 - date2).days
print(days // 7)

Output:

56 将字符串格式的日期转换为 Unix 时间戳

import datetime
stime = '15/05/2021'
print(datetime.datetime.strptime(stime, "%d/%m/%Y").timestamp())

Output:

1621017000.0

57 获取最后一个周日和周六的日期

from datetime import datetime, timedelta
def prior_week_end():
    return datetime.now() - timedelta(days=((datetime.now().isoweekday() + 1) % 7))
def prior_week_start():
    return prior_week_end() - timedelta(days=6)
print('Sunday', format(prior_week_start()))
print('Saturday', format(prior_week_end()))

Output:

Sunday 2021-05-09 13:13:30.057765
Saturday 2021-05-15 13:13:30.058912

58 检查对象是否属于 datetime.date 类型

import datetime
x = '2012-9-1'
y = datetime.date(2012, 9, 1)





    
print(isinstance(x, datetime.date))
print(isinstance(y, datetime.date))

Output:

False
True

59 获取特定日期的周数

import datetime
print(datetime.date(2020, 5, 15).isocalendar()[1])

Output:

60 获取 UTC 时间

from datetime import datetime
dt = datetime.utcnow()
print(dt)

Output:

2021-05-15 17:01:31.008808

61 获取本周的开始和结束日期

import pendulum
today = pendulum.now()
start = today.start_of('week')
print(start.to_datetime_string())
end = today.end_of('week')
print(end.to_datetime_string())

Output:

2021-05-10 00:00:00
2021-05-16 23:59:59

62 两个日期之间的差异（以分钟为单位）

from datetime import datetime
fmt = '%Y-%m-%d %H:%M:%S'
d1 = datetime.strptime('2010-01-01 17:31:22', fmt)
d2 = datetime.strptime('2010-01-03 17:31:22', fmt)
days_diff = d2 - d1
print(days_diff.days * 24 * 60)

Output:

63 将日期时间对象转换为日期字符串

import datetime
t = datetime.datetime(2020, 12, 23)
x = t.strftime('%m/%d/%Y')
print(x)

Output:

12/23/2020

64 获得上周五

from datetime import date
from datetime import timedelta
today = date.today()
offset = (today.weekday() - 4) % 7
friday = today - timedelta(days=offset)
print(friday)

Output:

2021-05-14

65 将 3 周添加到任何特定日期

import pendulum
dt = pendulum.datetime(2012, 2, 15)
dt = dt.add(weeks=3)
print(dt.to_date_string())

Output:

2012-03-07

66 在其他两个日期之间生成一个随机日期

import random
import time
def str_time_prop(start, end, time_format, prop):
    stime = time.mktime(time.strptime(start, time_format))
    etime = time.mktime(time.strptime(end, time_format))
    ptime = stime + prop * (etime - stime)
    return time.strftime(time_format, time.localtime(ptime))
def random_date(start, end, prop):
    return str_time_prop(start, end, '%m/%d/%Y %I:%M %p', prop)
print(random_date("1/1/2020 1:10 PM", "1/1/2021 1:10 AM", random.random()))

Output:

02/25/2020 08:26 AM

67 查找从今天开始的第一个星期一的日期

from dateutil.rrule import rrule, WEEKLY, MO
from datetime import date
next_monday = rrule(freq=WEEKLY, dtstart=date.today(), byweekday=MO, count=1)[0]
print(next_monday)

Output:

2021-05-17 00:00:00

68 两个日期之间的差异（以天为单位）

from datetime import date
d1 = date(2019, 8, 18)
d2 = date(2021, 12, 10)
days_diff = d2 - d1
print(days_diff.days)

Output:

69 向当前日期添加六个月

from datetime import datetime
from dateutil.relativedelta import *
date = datetime.now()
print(date)
date = date + relativedelta(months=+6)
print(date)

Output:

2021-05-15 13:48:52.135612
2021-11-15 13:48:52.135612

70 将数据时间对象转换为 Unix（时间戳）

import datetime
import time
# Saturday, October 10, 2015 10:10:00 AM
date_obj = datetime.datetime(2015, 10, 10, 10, 10)
print("Unix Timestamp: ", (time.mktime(date_obj.timetuple())))

Output:

Unix Timestamp: 1444452000.0

71 将年、月、日、时、分、秒的 N 个数字添加到当前日期时间

import datetime
from dateutil.relativedelta import relativedelta
add_days = datetime.datetime.today() + relativedelta(days=+6)
add_months = datetime.datetime.today() + relativedelta(months=+6)
add_years = datetime.datetime.today() + relativedelta(years=+6)
add_hours = datetime.datetime.today() + relativedelta(hours=+6)
add_mins = datetime.datetime.today() + relativedelta(minutes=+6)
add_seconds = datetime.datetime.today() + relativedelta(seconds=+6)
print("Current Date Time:", datetime.datetime.today())
print("Add 6 days:", add_days)
print("Add 6 months:", add_months)
print("Add 6 years:", add_years)
print("Add 6 hours:", add_hours)
print("Add 6 mins:", add_mins)
print("Add 6 seconds:", add_seconds)

Output:

Current Date Time: 2017-04-04 18:32:10.192671
Add 6 days: 2017-04-10 18:32:10.191671
Add 6 months: 2017-10-04 18:32:10.192671
Add 6 years: 2023-04-04 18:32:10.192671
Add 6 hours: 2017-04-05 00:32:10.192671
Add 6 mins: 2017-04-04 18:38:10.192671
Add 6 seconds: 2017-04-04 18:32:16.192671

72 获取指定开始日期和结束日期之间的日期范围

import datetime
start = datetime.datetime.strptime("2016-06-15", "%Y-%m-%d")





    
end = datetime.datetime.strptime("2016-06-30", "%Y-%m-%d")
date_array = \
    (start + datetime.timedelta(days=x) for x in range(0, (end-start).days))
for date_object in date_array:
    print(date_object.strftime("%Y-%m-%d"))

Output:

73 减去 N 个年、月、日、时、分、秒到当前日期时间

import datetime
from dateutil.relativedelta import relativedelta
sub_days = datetime.datetime.today() + relativedelta(days=-6)
sub_months = datetime.datetime.today() + relativedelta(months=-6)
sub_years = datetime.datetime.today() + relativedelta(years=-6)
sub_hours = datetime.datetime.today() + relativedelta(hours=-6)
sub_mins = datetime.datetime.today() + relativedelta(minutes=-6)





    
sub_seconds = datetime.datetime.today() + relativedelta(seconds=-6)
print("Current Date Time:", datetime.datetime.today())
print("Subtract 6 days:", add_days)
print("Subtract 6 months:", add_months)
print("Subtract 6 years:", add_years)
print("Subtract 6 hours:", add_hours)
print("Subtract 6 mins:", add_mins)
print("Subtract 6 seconds:", add_seconds)

Output:

Current Date Time: 2017-04-04 18:36:29.213046
Subtract 6 days: 2017-03-29 18:36:29.213046
Subtract 6 months: 2016-10-04 18:36:29.213046
Subtract 6 years: 2011-04-04 18:36:29.213046
Subtract 6 hours: 2017-04-04 12:36:29.213046
Subtract 6 mins: 2017-04-04 18:30:29.213046
Subtract 6 seconds: 2017-04-04 18:36:23.213046

74 获取指定年份和月份的月份第一天的工作日和月份的天数

import calendar
print("Year:2002 - Month:2")
month_range = calendar.monthrange(2002, 2)
print("Weekday of first day of the month:", month_range[0])
print("Number of days in month:", month_range[1])
print()
print("Year:2010 - Month:5")
month_range = calendar.monthrange(2010, 5)
print("Weekday of first day of the month:", month_range[0])
print("Number of days in month:", month_range[1])

Output:

Year:2002 - Month:2
Weekday of first day of the month: 4
Number of days in month: 28
Year:2010 - Month:5
Weekday of first day of the month: 5
Number of days in month: 31

75 打印特定年份的所有星期一

from datetime import date, timedelta
year = 2018
date_object = date(year, 1, 1)
date_object += timedelta(days=1-date_object.isoweekday())
while date_object.year == year:
    print(date_object)
    date_object += timedelta(days=7)

Output:

76 打印特定年份的日历

import calendar
cal_display = calendar.TextCalendar(calendar.MONDAY)
# Year: 2019
# Column width: 1
# Lines per week: 1 
# Number of spaces between month columns: 0
# No. of months per column: 2
print(cal_display.formatyear(2019, 1, 1, 0, 2))

Output:

略

77 从月份编号中获取月份名称

import calendar
import datetime
# Month name from number
print("Month name from number 5:")
month_num = 1
month_abre = datetime.date(2015, month_num, 1).strftime('%b')
month_name = datetime.date(2015, month_num, 1).strftime('%B')
print("Short Name:", month_abre)
print("Full  Name:", month_name)
print("\nList of all months from calendar")
# Print list of all months from calendar
for month_val in range(1, 13):
    print(calendar.month_abbr[month_val], "-", calendar.month_name[month_val])

Output:

Month name from number 5:
Short Name: Jan
Full Name: January
List of all months from calendar
Jan - January
Feb - February
Mar - March
Apr - April
May - May
Jun - June
Jul - July
Aug - August
Sep - September
Oct - October
Nov - November
Dec - December

78 从给定日期获取一周的开始和结束日期

from datetime import datetime, timedelta
date_str = '2018-01-14'
date_obj = datetime.strptime(date_str, '%Y-%m-%d')
start_of_week = date_obj - timedelta(days=date_obj.weekday())  # Monday
end_of_week = start_of_week + timedelta(days=6)  # Sunday
print(start_of_week)
print(end_of_week)

Output:

2018-01-08 00:00:00
2018-01-14 00:00:00

79 根据当前日期查找上一个和下一个星期一的日期

import datetime
today = datetime.date.today()
last_monday = today - datetime.timedelta(days=today.weekday())
coming_monday = today + datetime.timedelta(days=-today.weekday(), weeks=1)
print("Today:", today)
print("Last Monday:", last_monday)
print("Coming Monday:", coming_monday)

Output:

Today: 2018-01-21
Last Monday: 2018-01-15
Coming Monday: 2018-01-22

80 获取当前季度的第一个日期和最后一个日期

from datetime import datetime, timedelta
current_date = datetime.now()
current_quarter = round((current_date.month - 1) / 3 + 1)
first_date = datetime(current_date.year, 3 * current_quarter - 2, 1)
last_date = datetime(current_date.year, 3 * current_quarter + 1, 1)\
    + timedelta(days=-1)
print("First Day of Quarter:", first_date)
print("Last Day of Quarter:", last_date)

Output:

First Day of Quarter: 2018-01-01 00:00:00
Last Day of Quarter: 2018-03-31 00:00:00

图解爬虫，用几个最简单的例子带你入门Python爬虫

爬虫一直是Python的一大应用场景，差不多每门语言都可以写爬虫，但是程序员们却独爱Python。之所以偏爱Python就是因为她简洁的语法，我们使用Python可以很简单的写出一个爬虫程序。本篇博客将以Python语言，用几个非常简单的例子带大家入门Python爬虫。

一、本次目标：我们要提取出豆瓣电影-正在上映电影名称、评分、图片的信息，提取的站点 URL 为：https://movie.douban.com/cinema/nowplaying/beijing/，提取的结果我们以文件形式保存下来。

42 从工作日值中获取工作日名称

43 将 N 小时数添加到当前日期时间

44 从当前日期获取年、月、日、小时、分钟

45 获取特定月份和年份的最后一个星期日

46 查找特定日期的年份中的哪一天

47 查找当前日期是工作日还是周末

48 组合 datetime.date 和 datetime.time 对象

49 获得每月的第 5 个星期一

50 将日期时间对象转换为日期对象

51 获取没有微秒的当前日期时间

52 将 N 秒数添加到特定日期时间

53 从当前日期获取两位数的月份和日期

54 从特定日期获取月份数据的开始和结束日期

55 以周为单位的两个日期之间的差异

56 将字符串格式的日期转换为 Unix 时间戳

57 获取最后一个周日和周六的日期

58 检查对象是否属于 datetime.date 类型

59 获取特定日期的周数

60 获取 UTC 时间

61 获取本周的开始和结束日期

62 两个日期之间的差异（以分钟为单位）

63 将日期时间对象转换为日期字符串

64 获得上周五

65 (adsbygoogle = window.adsbygoogle || []).push({}); 将 3 周添加到任何特定日期

66 在其他两个日期之间生成一个随机日期

67 查找从今天开始的第一个星期一的日期

68 两个日期之间的差异（以天为单位）

69 向当前日期添加六个月

70 将数据时间对象转换为 Unix（时间戳）

71 将年、月、日、时、分、秒的 N 个数字添加到当前日期时间

72 获取指定开始日期和结束日期之间的日期范围

73 减去 N 个年、月、日、时、分、秒到当前日期时间

74 获取指定年份和月份的月份第一天的工作日和月份的天数

75 打印特定年份的所有星期一

76 打印特定年份的日历

77 从月份编号中获取月份名称

78 从给定日期获取一周的开始和结束日期

79 根据当前日期查找上一个和下一个星期一的日期

80 获取当前季度的第一个日期和最后一个日期

65 将 3 周添加到任何特定日期