# -*- coding: utf-8 -*-

#python 27

#xiaodeng

#python之模块datetime

#http://blog.sina.com.cn/s/blog_6c3748830100ypt9.html

#http://blog.sina.com.cn/s/blog_dd49240d0102w0y6.html



import datetime

'''

NAME:

datetime - Fast implementation of the datetime type.

'''

#help(datetime),datetime模块下的几个类：

'''

datetime.date

    .today()

datetime.time

datetime.datetime

    .now()

    .timedelta(days=1)

datetime.timedelta

datetime.tzinfo

'''

import datetime

import time

#今天日期

today=datetime.date.today()

print today#2015-09-05

#日期对象;date(year, month, day) --> date object

s=datetime.date(2015,9,1)

print s,type(s)#2015-09-01

#获取当前系统时间

date=datetime.datetime.now()

print date#2015-09-05 16:34:41.460000

#返回昨天的日期

def getYesterday():

    today=datetime.date.today()

    oneday=datetime.timedelta(days=1)

    yesterday=today-oneday

    return yesterday

#获取当前年份，月份等，是一个字符串

def getYear():

    year=str(datetime.date.today())[0:4]

    month=str(datetime.date.today())[5:7]

    return year,month

print 'getYear:',getYear()

#返回当前时间的时间戳

s=time.time()

print s

#计算2个日期的天数差

import datetime

d1=datetime.datetime(2015,9,1)

d2=datetime.datetime(2015,9,5)

print d2-d1#4 days, 0:00:00

s=(d2-d1).days

print s#4天

#计算当前时间向后10小时的时间

import datetime

d1=datetime.datetime.now()

d2=d1+datetime.timedelta(hours=10)#注意hours，是有s的

print d2.ctime()#Sun Sep  6 02:53:21 2015

#计算上个月的月份

import time

last_month = time.localtime()[1]-1 or 12

print last_month