python 時間轉換

import datetime

# 將字符串轉換成時間

start_time = '201808201000'
now_datetime = datetime.datetime.strptime(start_time, '%Y%m%d%H%M')
其中"%Y%m%d %H%M%S"爲time字符串的時間格式 Y爲年，m爲月，d爲天，H爲小時，M爲分鐘，S爲秒，執行轉化結果以下
2018-08-20 10:00:00

若是咱們要加的時間是天，當前時間加上datetime.timedelta(days=1)。datetime的timedelta方法實現
low_datetime = now_datetime + datetime.timedelta(days=1)

若是要加的時間是小時則以下，當前時間加上datetime.timedelta(hour

s=1)

low_datetime = now_datetime + datetime.timedelta(hours=1)

若是要加的時間是分鐘則以下，當前時間加上datetime.timedelta(minutes=1)

low_datetime = now_datetime + datetime.timedelta(minutes=1)
print(low_datetime)

若是加的時間是秒的話，以下當前時間加上datetime.timedelta(seconds=1)

low_datetime = now_datetime + datetime.timedelta(seconds=1)
print(low_datetime)

時間轉換成字符串

low_datetime = now_datetime - datetime.timedelta(minutes=2)
low_datetime = low_datetime.strftime('%Y%m%d%H%M')
print(low_datetime)

import datetime
from datetime import timedelta
now = datetime.datetime.now()
#今天
today = now
#昨天
yesterday = now - timedelta(days=1)
#明天
tomorrow = now + timedelta(days=1)<br><br>#當前季度 
now_quarter = now.month / 3 if now.month % 3 == 0 else now.month / 3 + 1
#本週第一天和最後一天
this_week_start = now - timedelta(days=now.weekday())
this_week_end = now + timedelta(days=6-now.weekday())
#上週第一天和最後一天
last_week_start = now - timedelta(days=now.weekday()+7)
last_week_end = now - timedelta(days=now.weekday()+1)
#本月第一天和最後一天
this_month_start = datetime.datetime(now.year, now.month, 1)
this_month_end = datetime.datetime(now.year, now.month + 1, 1) - timedelta(days=1)
#上月第一天和最後一天
last_month_end = this_month_start - timedelta(days=1)
last_month_start = datetime.datetime(last_month_end.year, last_month_end.month, 1)
#本季第一天和最後一天
month = (now.month - 1) - (now.month - 1) % 3 + 1
this_quarter_start = datetime.datetime(now.year, month, 1)
this_quarter_end = datetime.datetime(now.year, month + 3, 1) - timedelta(days=1)
#上季第一天和最後一天
last_quarter_end = this_quarter_start - timedelta(days=1)
last_quarter_start = datetime.datetime(last_quarter_end.year, last_quarter_end.month - 2, 1)
 #本年第一天和最後一天
this_year_start = datetime.datetime(now.year, 1, 1)
this_year_end = datetime.datetime(now.year + 1, 1, 1) - timedelta(days=1)

#去年第一天和最後一天
last_year_end = this_year_start - timedelta(days=1)
last_year_start = datetime.datetime(last_year_end.year, 1, 1)