[英]Converting and comparing 2 datetimes
我需要帮助,尝试将字符串转换为日期时间,然后进行比较以查看其是否少于3天。 我已经尝试了time类和datetime类,但是我一直遇到相同的错误:
TypeError: unsupported operand type(s) for -: 'str' and 'str'
这是我尝试过的代码:
def time_calculation():
time1 = "2:00 PM 5 Oct 2016"
time2 = "2:00 PM 4 Oct 2016"
time3 = "2:00 PM 1 Oct 2016"
timeNow = time.strftime("%Y%m%d-%H%M%S")
#newtime1 = time.strftime("%Y%m%d-%H%M%S", time.strptime(time1, "%I:%M %p %d %b %Y"))
newtime1 = datetime.strptime(time1, "%I:%M %p %d %b %Y").strftime("%Y%m%d-%H%M%S")
print("the new time1 is {}".format(newtime1))
#newtime2 = time.strftime("%Y%m%d-%H%M%S", time.strptime(time2, "%I:%M %p %d %b %Y"))
newtime2 = datetime.strptime(time2, "%I:%M %p %d %b %Y").strftime("%Y%m%d-%H%M%S")
print("the new time2 is {}".format(newtime2))
#newtime3 = time.strftime("%Y%m%d-%H%M%S", time.strptime(time3, "%I:%M %p %d %b %Y"))
newtime3 = datetime.strptime(time3, "%I:%M %p %d %b %Y").strftime("%Y%m%d-%H%M%S")
print("the new time3 is {}".format(newtime3))
timeList = []
timeList.append(newtime1)
timeList.append(newtime2)
timeList.append(newtime3)
for ele in timeList:
deltaTime = ele - timeNow
if deltaTime.days < 4:
print("This time was less than 4 days old {}\n".format(ele.strftime("%Y%m%d-%H%M%S")))
被注释掉的部分是我在时间上所做的,而其他部分是在日期时间上。
该错误发生在我尝试将列表中的每个时间与当前时间进行比较的那一行,但是它将它们作为字符串而不是日期时间,并且不会减去它们,所以我可以对它们进行比较。 (在底部的for循环中。)
确实,不要转换回字符串,而是使用datetime
对象。 如错误消息str - str
所指出, str - str
不是已定义的操作(从另一个字符串中减去一个字符串是什么意思?):
"s" - "s" # TypeError
而是使用datetime.now()
初始化timeNow
, datetime
实例支持减法。 第二个建议是,从timeNow
减去ele
,而不是从ele
减去timeNow
:
def time_calculation():
# snipped for brevity
timeNow = datetime.now()
# snipped
for ele in timeList:
deltaTime = timeNow - ele
if deltaTime.days < 4:
print("This time was less than 4 days old {}\n".format(ele.strftime("%Y%m%d-%H%M%S")))
打印输出:
time_calculation()
the new time1 is 2016-10-05 14:00:00
the new time2 is 2016-10-04 14:00:00
the new time3 is 2016-10-01 14:00:00
This time was less than 4 days old 20161005-140000
This time was less than 4 days old 20161004-140000
我猜是你在追求什么。
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.