day22-时间模块、random模块、os模块、sys模块

文章目录

• 时间模块
• • time
  • datetime
• random模块
• os模块
• sys模块
• 作业

时间模块

time

import time

时间分为三种格式：
1、时间戳：从1970年到现在经过的秒数
   作用：用于时间间隔的计算

print(time.time()) # 1612522068.0428286

2、按照某种格式显示的时间：2020-03-30 11:11:11
   作用：用于展示时间

print(time.strftime('%Y-%m-%d %H:%M:%S %p')) # 2021-02-05 18:48:09 PM
print(time.strftime('%Y-%m-%d %X')) # 2021-02-05 18:48:23

3、结构化的时间
   作用：用于单独获取时间的某一部分

res=time.localtime()
	print(res)
	print(res.tm_year)
	print(res.tm_yday)

datetime

import datetime

print(datetime.datetime.now()) # 2021-02-05 18:51:00.268453
print(datetime.datetime.now() + datetime.timedelta(days=3)) # 2021-02-08 18:51:15.130269
print(datetime.datetime.now() + datetime.timedelta(weeks=1)) # 2021-02-12 18:51:23.969053

时间模块需要掌握的操作
1、时间格式的转换
struct_time->时间戳

import time
s_time=time.localtime()
print(time.mktime(s_time))

时间戳->struct_time

tp_time=time.time()
print(time.localtime(tp_time)) 
# time.struct_time(tm_year=2021, tm_mon=2, tm_mday=5, tm_hour=18, tm_min=52, tm_sec=36, tm_wday=4, tm_yday=36, tm_isdst=0)

补充：世界标准时间与本地时间

print(time.localtime())
# time.struct_time(tm_year=2021, tm_mon=2, tm_mday=5, tm_hour=18, tm_min=54, tm_sec=18, tm_wday=4, tm_yday=36, tm_isdst=0)
print(time.gmtime()) # 世界标准时间，了解
# time.struct_time(tm_year=2021, tm_mon=2, tm_mday=5, tm_hour=10, tm_min=54, tm_sec=36, tm_wday=4, tm_yday=36, tm_isdst=0)
print(time.localtime(333333333))
# time.struct_time(tm_year=1980, tm_mon=7, tm_mday=25, tm_hour=8, tm_min=35, tm_sec=33, tm_wday=4, tm_yday=207, tm_isdst=0)
print(time.gmtime(333333333))
# time.struct_time(tm_year=1980, tm_mon=7, tm_mday=25, tm_hour=0, tm_min=35, tm_sec=33, tm_wday=4, tm_yday=207, tm_isdst=0)

struct_time->格式化的字符串形式的时间

s_time=time.localtime()
	print(time.strftime('%Y-%m-%d %H:%M:%S',s_time))
	
	print(time.strptime('1988-03-03 11:11:11','%Y-%m-%d %H:%M:%S'))

!!!真正需要掌握的只有一条：format string<------>timestamp

‘1988-03-03 11:11:11’+7

format string—>struct_time—>timestamp

struct_time=time.strptime('1988-03-03 11:11:11','%Y-%m-%d %H:%M:%S')
	timestamp=time.mktime(struct_time)+7*86400
	print(timestamp)

format string<—struct_time<—timestamp

res=time.strftime('%Y-%m-%d %X',time.localtime(timestamp))
	print(res)
	
	time.sleep(3)

了解知识

import time
print(time.asctime()) # Fri Feb  5 18:57:30 2021


import datetime
print(datetime.datetime.now()) # 2021-02-05 18:58:00.029894
print(datetime.datetime.utcnow()) # 2021-02-05 10:57:45.603007

print(datetime.datetime.fromtimestamp(333333)) # 1970-01-05 04:35:33

random模块

import random

print(random.random())  # (0,1)----float    大于0且小于1之间的小数
print(random.randint(1, 3))  # [1,3]    大于等于1且小于等于3之间的整数

print(random.randrange(1, 3))  # [1,3)    大于等于1且小于3之间的整数

print(random.choice([111, 'aaa', [4, 5]]))  # 1或者23或者[4,5]

print(random.sample([111, 'aaa', 'ccc', 'ddd'], 2))  # 列表元素任意2个组合

print(random.uniform(1, 3))  # 大于1小于3的小数，如1.927109612082716

item = [1, 3, 5, 7, 9]
random.shuffle(item)  # 打乱item的顺序,相当于"洗牌"
print(item)

应用：随机验证码

res = ''
for i in range(6):
    从26大写字母中随机取出一个 = chr(random.randint(65, 90))
    从10个数字中随机取出一个 = str(random.randint(0, 9))

    随机字符 = random.choice([从26大写字母中随机取出一个, 从10个数字中随机取出一个])
    res += 随机字符


def make_code(size=4):
    res = ''
    for i in range(size):
        s1 = chr(random.randint(65, 90))
        s2 = str(random.randint(0, 9))
        res += random.choice([s1, s2])
    return res


print(make_code(6))

os模块

import os

# 获取某一个文件夹下所有的子文件以及子文件夹的名字
res = os.listdir('.')
print(res)


size = os.path.getsize(
    r'/Users/linhaifeng/PycharmProjects/s14/day22/01 时间模块.py')
print(size)


os.remove()  删除一个文件
os.rename("oldname", "newname")  重命名文件/目录


应用程序----》"ls /"
os.system("ls /")

规定：key与value必须都为字符串

os.environ['aaaaaaaaaa'] = '111'
print(os.environ)


print(os.path.dirname(r'/a/b/c/d.txt'))
print(os.path.basename(r'/a/b/c/d.txt'))


print(os.path.isfile(r'笔记.txt'))
print(os.path.isfile(r'aaa'))
print(os.path.isdir(r'aaa'))

print(os.path.join('a', '/', 'b', 'c', 'd'))


推荐用这种
BASE_DIR = os.path.dirname(os.path.dirname(__file__))
print(BASE_DIR)


BASE_DIR = os.path.normpath(os.path.join(
    __file__,
    '..',
    '..'
))
print(BASE_DIR)

在python3.5之后，推出了一个新的模块pathlib

res = Path(__file__).parent.parent
print(res)


res = Path('/a/b/c') / 'd/e.txt'
print(res)

print(res.resolve())

sys模块

import sys

python3.8 run.py 1 2 3
sys.argv获取的是解释器后参数值
print(sys.argv)

src_file = input('源文件路径: ').strip()
dst_file = input('目标文件路径: ').strip()

src_file = sys.argv[1]
dst_file = sys.argv[2]
# 判断

with open(r'%s' % src_file, mode='rb') as read_f,
        open(r'%s' % dst_file, mode='wb') as write_f:
    for line in read_f:
        write_f.write(line)

python3.8 run.py src_file dst_file


print('[%-50s]' % '#')
print('[%-50s]' % '##')
print('[%-50s]' % '###')


res = ''
for i in range(50):
    res += '#'
    time.sleep(0.5)
    print('
[%-50s]' % res, end='')


def progress(percent):
    if percent > 1:
        percent = 1
    res = int(50 * percent) * '#'
    print('
[%-50s] %d%%' % (res, int(100 * percent)), end='')


recv_size = 0
total_size = 1025011

while recv_size < total_size:
    time.sleep(0.01)  # 下载了1024个字节的数据

    recv_size += 1024  # recv_size=2048

    # 打印进度条
    # print(recv_size)
    percent = recv_size / total_size  # 1024 / 333333
    progress(percent)

作业

1、检索文件夹大小的程序，要求执行方式如下
    python3.8 run.py 文件夹
2、明天上午日考：随机验证码、模拟下载以及打印进度条、文件copy脚本