Python time datetime常用时间处理方法

常用时间转换及处理函数：

import datetime  # 获取当前时间  d1 = datetime.datetime.now()  print d1  # 当前时间加上半小时  d2 = d1 + datetime.timedelta(hours=0.5)  print d2  # 格式化字符串输出  d3 = d2.strftime('%Y-%m-%d %H:%M:%S')  print d3  # 将字符串转化为时间类型  d4 = datetime.datetime.strptime(date,'%Y-%m-%d %H:%M:%S.%f')  print d4

获取本周和本月第一天的日期：

# -*- coding:utf-8 -*-  import datetime  def first_day_of_month():      '''      获取本月第一天      :return:      '''      # now_date = datetime.datetime.now()      # return (now_date + datetime.timedelta(days=-now_date.day + 1)).replace(hour=0, minute=0, second=0,      # microsecond=0)      return datetime.date.today() - datetime.timedelta(days=datetime.datetime.now().day - 1)  def first_day_of_week():      '''      获取本周第一天      :return:      '''      return datetime.date.today() - datetime.timedelta(days=datetime.date.today().weekday())  if __name__ == "__main__":      this_week = first_day_of_week()      last_week = this_week - datetime.timedelta(days=7)      this_month = first_day_of_month()      last_month = this_month - datetime.timedelta(days=(this_month - datetime.timedelta(days=1)).day)      print this_week      print last_week      print this_month      print last_month