python 日期大小比較

輸入的日期跟當前日期比較大小 

日期在python中 存在time,datetime，string三種形式轉化如下 

#str轉time 

time.strptime('2018-09-28',"%Y-%m-%d")

#str轉datetime

datetime.datetime.striptime('2018-09-28',"%Y-%m-%d")

#time 轉string 

time.strftime("%y-%m-%d",time.localtime())

需求實現：

import datetime
import time
#將日期字符串轉爲時間再比較，time，datetime,str
def valid_date(timestr):
    #獲取當前時間日期
    nowTime_str = datetime.datetime.now().strftime('%Y-%m-%d') 
    print(nowTime_str)
    #mktime參數爲struc_time,將日期轉化爲秒，
    e_time = time.mktime(time.strptime(nowTime_str,"%Y-%m-%d"))
    print(e_time)
    try:
        s_time = time.mktime(time.strptime(timestr, '%Y-%m-%d'))
        print(s_time)
        #日期轉化爲int比較
        diff = int(s_time)-int(e_time)
        print(diff)
        if diff >= 0:
            return 1
        else:
            print('所查日期不能小於當前時間！！！')
            return 0
    except Exception as e:
        print(e)
        return 0
if __name__=='__main__':
    valid_date("2018-10-07")

執行結果：