Python Date and Time Manipulation Examples

1. Get the current date and time

from datetime import datetime
now = datetime.now()
print("当前时间:", now)

2. Format and output the current time

formatted_time = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
print("格式化后的当前时间:", formatted_time)

3. Calculate the number of days between two dates

from datetime import datetime
date1 = datetime(2025, 5, 1)
date2 = datetime(2025, 6, 1)
difference = (date2 - date1).days
print(f"{date1} 和 {date2} 之间相差 {difference} 天")

4. Convert a string to a date object

from datetime import datetime
date_str = "2025-05-01"
date_obj = datetime.strptime(date_str, "%Y-%m-%d")
print("日期对象:", date_obj)

5. Convert a date object to a string

from datetime import datetime
date_obj = datetime.now()
date_str = date_obj.strftime("%Y-%m-%d")
print("日期字符串:", date_str)

6. Get today's date

from datetime import date
today = date.today()
print("今天的日期:", today)

7. Add one day to the current date

from datetime import datetime, timedelta
now = datetime.now()
tomorrow = now + timedelta(days=1)
print("明天的日期:", tomorrow)

8. Subtract one hour from the current time

from datetime import datetime, timedelta
an_hour_ago = datetime.now() - timedelta(hours=1)
print("一小时前的时间:", an_hour_ago)

9. Determine whether a year is a leap year

import calendar
year = 2024
if calendar.isleap(year):
    print(f"{year} 是闰年")
else:
    print(f"{year} 不是闰年")

10. Get the first and last day of the current month

from datetime import datetime, timedelta
first_day = datetime.today().replace(day=1)
last_day = (first_day + timedelta(days=32)).replace(day=1) - timedelta(days=1)
print("本月第一天:", first_day.date())
print("本月最后一天:", last_day.date())

11. Create a simple countdown timer

import time
def countdown(t):
    while t:
        mins, secs = divmod(t, 60)
        timer = '{:02d}:{:02d}'.format(mins, secs)
        print(timer, end="\r")
        time.sleep(1)
        t -= 1
countdown(5)
print("计时结束")

12. Schedule a task using the sched module

import sched, time
scheduler = sched.scheduler(time.time, time.sleep)
def print_event(name):
    print(f"事件: {name} 在 {time.time()} 执行")
print('开始:', time.time())
scheduler.enter(2, 1, print_event, ('事件1',))
scheduler.run()

13. Get the calendar for a specific month

import calendar
year = 2025
month = 5
print(calendar.month(year, month))

14. Convert a timestamp to a datetime

import time
from datetime import datetime
timestamp = time.time()
print("时间戳:", timestamp)
date_time = datetime.fromtimestamp(timestamp)
print("日期时间:", date_time)

15. Convert a datetime to a timestamp

from datetime import datetime
date_time_str = '2025-05-05 12:00:00'
date_time_obj = datetime.strptime(date_time_str, '%Y-%m-%d %H:%M:%S')
timestamp = date_time_obj.timestamp()
print("时间戳:", timestamp)

16. Determine the day of the week for a given date

from datetime import datetime
date = datetime(2025, 5, 5)
print(date.strftime("%A"))  # 输出星期几

17. Calculate a date after adding a number of working days (excluding weekends)

from datetime import datetime, timedelta
def add_working_days(start_date, days):
    current_date = start_date
    added_days = 0
    while added_days < days:
        current_date += timedelta(days=1)
        if current_date.weekday() < 5:  # 排除周末
            added_days += 1
    return current_date
start_date = datetime(2025, 5, 5)
print(add_working_days(start_date, 10))  # 10个工作日后的日期

18. Calculate the number of weeks between two dates

from datetime import datetime
date1 = datetime(2025, 5, 1)
date2 = datetime(2025, 6, 1)
weeks_difference = (date2 - date1).days // 7
print(f"{date1} 和 {date2} 之间相差 {weeks_difference} 周")

19. Get the Monday and Sunday of the current week

from datetime import datetime, timedelta
today = datetime.today()
start_of_week = today - timedelta(days=today.weekday())
end_of_week = start_of_week + timedelta(days=6)
print("本周周一:", start_of_week.date())
print("本周周日:", end_of_week.date())

20. Implement a simple delay using time.sleep()

import time
print("开始")
time.sleep(2)  # 等待2秒
print("2秒后...")