用Python解析时间字符串？

Question

我正在编写一个应用程序，涉及用户输入以下格式的时间：

1m30s # 1 Minute,  30 Seconds

3m15s # 3 Minutes, 15 Seconds

2m25s # 2 Minutes, 25 Seconds

2m    # 2 Minutes

55s   # 55 Seconds

数据可以有一个“分钟标识”，一个“秒钟标识”或两者都有。将这些字符串解析成类似以下格式的格式的正确方法是什么：

{
    "minutes" : 3
    "seconds" : 25
}

- Mike Trpcic

Answer 1

import re

tests=['1m30s','3m15s','2m25s','2m','55s']
for time_str in tests:
    match=re.match('(?:(\d*)m)?(?:(\d*)s)?',time_str)
    if match:
        minutes = int(match.group(1) or 0)
        seconds = int(match.group(2) or 0)
        print({'minutes':minutes,
               'seconds':seconds})

# {'seconds': 30, 'minutes': 1}
# {'seconds': 15, 'minutes': 3}
# {'seconds': 25, 'minutes': 2}
# {'seconds': 0, 'minutes': 2}
# {'seconds': 55, 'minutes': 0}

- unutbu

Answer 2

正则表达式来帮忙！

>>> import re
>>> minsec = re.compile(r'(?P<minutes>\d+)m(?P<seconds>\d+)s')
>>> result = minsec.match('1m30s')        
>>> result.groupdict()
{'seconds': '30', 'minutes': '1'}

编辑：这是一种改进后的解决方案：

import re
pattern = r'(?:(?P<minutes>\d+)m)?(?:(?P<seconds>\d+)s)?'

minsec = re.compile(pattern)

def parse(s, pat=minsec):
    return pat.match(s).groupdict()

tests = ['1m30s', '30s', '10m29s']
for t in tests:
    print '---'
    print ' in:', t
    print 'out:', parse(t)

输出：

---
 in: 1m30s
out: {'seconds': '30', 'minutes': '1'}
---
 in: 30s
out: {'seconds': '30', 'minutes': None}
---
 in: 10m29s
out: {'seconds': '29', 'minutes': '10'}

- jathanism

---

不错！我也在准备类似的回复，但你的更好。我从没听说过可以这样命名匹配组。 - Colin