Python-基礎-時間日期處理小結涉及對象1. datetime
2. timestamp
3. time tuple
4. string
5. date
datetime基本操作1. 獲取當前datetime
2. 獲取當天date
3. 獲取明天/前N天
4. 獲取當天開始和結束時間(00:00:00 23:59:59)
5. 獲取兩個datetime的時間差
6. 獲取本周/本月/上月最后一天
關系轉換
關系轉換例子datetime <=> string
datetime <=> timetuple
datetime <=> date
datetime <=> timestamp
原則, 以datetime
為中心, 起點或中轉, 轉化為目標對象, 涵蓋了大多數業(yè)務場景中需要的日期轉換處理
步驟:
- 掌握幾種對象及其關系2. 了解每類對象的基本操作方法3. 通過轉化關系轉化
涉及對象
datetime
import datetime
now = datetime.datetime.now()
nowdatetime.datetime(2015, 1, 12, 23, 9, 12, 946118)
type(now)<type 'datetime.datetime'>timestamp
import time
time.time()
1421075455.568243time tuple
import time
time.localtime()
time.struct_time(tm_year=2015, tm_mon=1, tm_mday=12, tm_hour=23, tm_min=10, tm_sec=30, tm_wday=0, tm_yday=12, tm_isdst=0)string
import datetime
datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S")
'2015-01-12 23:13:08'date
import datetime
datetime.datetime.now().date()
datetime.date(2015, 1, 12)
datetime基本操作
獲取當前datetime
import datetime
datetime.datetime.now()
datetime.datetime(2015, 1, 12, 23, 26, 24, 475680)獲取當天date
datetime.date.today()
datetime.date(2015, 1, 12)獲取明天/前N天
明天
datetime.date.today() + datetime.timedelta(days=1)
datetime.date(2015, 1, 13)
三天前
datetime.datetime.now()
datetime.datetime(2015, 1, 12, 23, 38, 55, 492226)
datetime.datetime.now() - datetime.timedelta(days=3)
datetime.datetime(2015, 1, 9, 23, 38, 57, 59363)
獲取當天開始和結束時間(00:00:00 23:59:59)
datetime.datetime.combine(datetime.date.today(), datetime.time.min)
datetime.datetime(2015, 1, 12, 0, 0)
datetime.datetime.combine(datetime.date.today(), datetime.time.max)
datetime.datetime(2015, 1, 12, 23, 59, 59, 999999)獲取兩個datetime的時間差
(datetime.datetime(2015,1,13,12,0,0) - datetime.datetime.now()).total_seconds()
44747.768075獲取本周/本月/上月最后一天
本周
today = datetime.date.today()
todaydatetime.date(2015, 1, 12)
sunday = today + datetime.timedelta(6 - today.weekday())
sundaydatetime.date(2015, 1, 18)
本月
import calendar
today = datetime.date.today()
_, last_day_num = calendar.monthrange(today.year, today.month)
last_day = datetime.date(today.year, today.month, last_day_num)
last_daydatetime.date(2015, 1, 31)
獲取上個月的最后一天(可能跨年)
import datetime
today = datetime.date.today()
first = datetime.date(day=1, month=today.month, year=today.year)
lastMonth = first - datetime.timedelta(days=1)
關系轉換
幾個關系之間的轉化
Datetime Object / String / timestamp / time tuple
關系轉換例子
datetime <=> string
datetime -> string
import datetime
datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S")
'2015-01-12 23:13:08'
string -> datetime
import datetime
datetime.datetime.strptime("2014-12-31 18:20:10", "%Y-%m-%d %H:%M:%S")
datetime.datetime(2014, 12, 31, 18, 20, 10)
datetime <=> timetuple
datetime -> timetuple
import datetime
datetime.datetime.now().timetuple()
time.struct_time(tm_year=2015, tm_mon=1, tm_mday=12, tm_hour=23, tm_min=17, tm_sec=59, tm_wday=0, tm_yday=12, tm_isdst=-1)
timetuple -> datetime
timetuple => timestamp => datetime [看后面datetime<=>timestamp]
datetime <=> date
datetime -> date
import datetime
datetime.datetime.now().date()
datetime.date(2015, 1, 12)
date -> datetime
datetime.date.today()datetime.date(2015, 1, 12)
today = datetime.date.today()
datetime.datetime.combine(today, datetime.time())
datetime.datetime(2015, 1, 12, 0, 0)
datetime.datetime.combine(today, datetime.time.min)
datetime.datetime(2015, 1, 12, 0, 0)
datetime <=> timestamp
datetime -> timestamp
now = datetime.datetime.now()
timestamp = time.mktime(now.timetuple())
timestamp1421077403.0
timestamp -> datetime
datetime.datetime.fromtimestamp(1421077403.0)
datetime.datetime(2015, 1, 12, 23, 43, 23)
