Python 时间格式转换

Python time, datetime模块常用方法

1、使用time模块，获取当前时间戳
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import time
time.time()
Out[3]: 1546046383.663

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2、将一个时间戳转化为结构化的元组  struct_time
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time.localtime(1546046383.663)
Out[4]: time.struct_time(tm_year=2018, tm_mon=12, tm_mday=29, tm_hour=9, tm_min=19, tm_sec=43, tm_wday=5, tm_yday=363, tm_isdst=0)

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3、已知时间戳，格式化字符串形式的时间输出
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time.strftime('%Y-%m-%d %H:%M:%S',time.localtime(1546046383.663))
Out[5]: '2018-12-29 09:19:43'

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4、直接格式化输出当前时间
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time.strftime('%Y-%m-%d %H:%M:%S')
Out[6]: '2018-12-29 09:27:50'

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5、获取毫秒级精度的时间，使用datetime模块
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import datetime
datetime.datetime.now()
Out[8]: datetime.datetime(2018, 12, 29, 9, 30, 38, 269000)
datetime.datetime.now().isoformat()
Out[9]: '2018-12-29T09:31:11.487000'
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等效方法
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datetime.datetime.today().isoformat()
Out[16]: '2018-12-29T09:38:19.502000'
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6、从时间戳转到格式化时间字符串，精确到毫秒
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datetime.datetime.fromtimestamp(time.time()).strftime('%Y-%m-%d %H:%M:%S.%f')
Out[12]: '2018-12-29 09:33:06.735000'

datetime.datetime.fromtimestamp(1546046383.663).strftime('%Y-%m-%d %H:%M:%S.%f')
Out[13]: '2018-12-29 09:19:43.663000'
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7、将结构化的元组时间格式转为时间戳格式, time.maketime(元组类型时间)
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time.mktime(datetime.datetime.now().timetuple())
Out[21]: 1546047923.0
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8、字符串格式的时间提取，转为结构化元组格式，进而转化为时间戳格式。 strptime(时间字符串， 时间格式)
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time.strptime('2018-12-29 09:49:36','%Y-%m-%d %H:%M:%S')
Out[22]: time.struct_time(tm_year=2018, tm_mon=12, tm_mday=29, tm_hour=9, tm_min=49, tm_sec=36, tm_wday=5, tm_yday=363, tm_isdst=-1)

time.mktime(time.strptime('2018-12-29 09:49:36','%Y-%m-%d %H:%M:%S'))
Out[23]: 1546048176.0
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