继续在日期时间 Python 中不起作用

Question

我正在尝试编写一个程序来打印两个给定日期之间的所有星期二，并排除劳动节和感恩节假期。然而，当我使用继续跳转时，它打破了循环。

import datetime

def getDates():
     StartDate = datetime.datetime(2020, 1, 1)
     EndDate = datetime.datetime(2020, 12, 31)
     LaborDay = datetime.datetime(2020, 9, 7)
     Thanksgiving_Start = datetime.datetime(2020, 11, 23)
     Thanksgiving_End = datetime.datetime(2020, 11, 28)
     CurrentDate = StartDate
     days = int((EndDate - StartDate).days)
     print(StartDate.strftime("%Y-%m-%d"))
     for NextDate in range(days):
          NextDate = CurrentDate + datetime.timedelta(days=7)
          if NextDate == LaborDay:
               continue
          if Thanksgiving_Start <= NextDate <= Thanksgiving_End:
               continue
          if NextDate > EndDate:
               break
          print(NextDate.strftime("%Y-%m-%d"))
          CurrentDate = NextDate

 getDates()

Answer 1

如果您使用 print()，您会看到 continue 正在按预期工作。

def getDates():
     StartDate = datetime.datetime(2020, 1, 1)
     EndDate = datetime.datetime(2020, 12, 31)
     LaborDay = datetime.datetime(2020, 9, 7)
     Thanksgiving_Start = datetime.datetime(2020, 11, 23)
     Thanksgiving_End = datetime.datetime(2020, 11, 28)
     CurrentDate = StartDate
     days = int((EndDate - StartDate).days)
     print(StartDate.strftime("%Y-%m-%d"))
     for NextDate in range(days):
          NextDate = CurrentDate + datetime.timedelta(days=7)
          if NextDate == LaborDay:
              #labor day is in day 7 from septemeber, this day is not multiple of seven
              #starting from StartDate, so it is impossible that is going to evaluate
              # to true
              print("Continue is working first statement")
              continue
          if Thanksgiving_Start <= NextDate <= Thanksgiving_End:
              print("Continue is working second statment")
              continue
          if NextDate > EndDate:
               break
          print(NextDate.strftime("%Y-%m-%d"))
          CurrentDate = NextDate
         

getDates()

Answer 2

问题是一旦遇到第二种情况，就没有设置CurrentDate。

实际上，您正在混合两种不同的更改方式NextDate。它由范围内的循环设置，但随后立即设置为与 CurrentDate 相关的值。选择一个并坚持下去；否则你一定会运行陷入混乱。

例如，在这里您可以将 for 的外观更改为 while True 循环（或更好：while NextData <= EndDate）；将 NextDate 增加 7 天；并从整个程序中删除 CurrentDate。

这样应该更容易推理。

继续在日期时间 Python 中不起作用

Continue Does Not Work in Python with datetime

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