Python - 以 YYYY-MM-DD 格式获取昨天的日期作为字符串
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Python - Get Yesterday's date as a string in YYYY-MM-DD format
提问by Jacob
As an input to an API request I need to get yesterday's date as a string in the format YYYY-MM-DD. I have a working version which is:
作为 API 请求的输入，我需要获取昨天的日期作为格式的字符串YYYY-MM-DD。我有一个工作版本，它是：
yesterday = datetime.date.fromordinal(datetime.date.today().toordinal()-1)
report_date = str(yesterday.year) + \
('-' if len(str(yesterday.month)) == 2 else '-0') + str(yesterday.month) + \
('-' if len(str(yesterday.day)) == 2 else '-0') + str(yesterday.day)
There must be a more elegant way to do this, interested for educational purposes as much as anything else!
必须有一种更优雅的方式来做到这一点，对教育目的和其他任何事情都感兴趣！
采纳答案by Kasramvd
You Just need to subtract one day from today's date. datetime.timedelta(1)will gieve you a timedeltaobjectwhich is a duration of one day and is subtractable from datetimeobject. Then you can use datetime.strftimein orer to convert the date object to string based on your espected format:
你只需要从今天的日期减去一天。datetime.timedelta(1)会给你一个持续时间为一天的timedelta对象，并且可以从datetime对象中减去。然后您可以datetime.strftime在 orer中使用根据您预期的格式将日期对象转换为字符串：
>>> from datetime import datetime, timedelta
>>> datetime.strftime(datetime.now() - timedelta(1), '%Y-%m-%d')
'2015-05-26'
Note that instead of calling the datetime.strftimefunction, you can also directly use strftimemethod of datetimeobjects:
请注意datetime.strftime，您也可以直接使用对象的strftime方法，而不是调用函数datetime：
>>> (datetime.now() - timedelta(1)).strftime('%Y-%m-%d')
'2015-05-26'
回答by Paul Rubel
>>> import datetime
>>> datetime.date.fromordinal(datetime.date.today().toordinal()-1).strftime("%F")
'2015-05-26'
回答by theRahulMody
An alternative answer that uses today()method to calculate current date and then subtracts one using timedelta(). Rest of the steps remain the same.
另一种答案是使用today()method 来计算当前日期，然后使用timedelta(). 其余步骤保持不变。
https://docs.python.org/3.7/library/datetime.html#timedelta-objects
https://docs.python.org/3.7/library/datetime.html#timedelta-objects
from datetime import date, timedelta
today = date.today()
yesterday = today - timedelta(days = 1)
print(today)
print(yesterday)
Output:
2019-06-14
2019-06-13
