def exception_test():

    try:

        x = float(input("请输入被除数："))

        y = float(input("请输入除数:"))

        z = x/y

        print(z)

    except ZeroDivisionError:

        print("除数不能为零！")

    # except ValueError:

    #     print("数值类型错误")

    else:

        print("没有捕获到对应的异常")

    finally:

        print("计算结束。。。")

def os_file_test():

    import os

    print(os.listdir())  # 目录列表

    print(os.getcwd())  # 当前目录

    print(os.path.exists("D:\Demo"))  # 判断目录

    f = open("./test.txt")

    # res1 = f.read()

    # print(res1)

    # res2 = f.readline()

    # print(res2)

    res3 = f.readlines()

    print(res3)

def time_test():

    import time

    for i in range(10):

        print(i)

        time.sleep(0.01)

    cur_time = time.time()

    print(cur_time)

    # 转为时间戳

    print(time.mktime(time.localtime()))

    # 转为特定格式

    print(time.asctime(time.localtime()))

    print(time.ctime(int(cur_time)))

    # 转换成时间字符串

    print(time.strftime("%Y-%m-%d %H:%M:%S", time.localtime()))

    print(time.strftime("%Y-%m-%d %X", time.localtime()))

    # 转换成时间字符穿

    str_time = time.strftime("%Y-%m-%d %X", time.localtime())

    print(time.strptime(str_time, "%Y-%m-%d %H:%M:%S"))

def random_test():

    import random

    # 0-1随机数

    print(random.random())

    # 一定范围的随机数

    print(random.uniform(2, 3))

    # 一定范围的整数

    print(random.randint(2, 4))  # 包括2,4

    # 序列中获取一个随机数

    print(random.randrange(10, 100, 2))  # 10,12,14...,96,98

    # random.choice() 是从序列中获取一个随机元素,可以是字符串，元组，列表等

    print(random.choice("python test"))

    print(random.choice(["1", "2", "3", "4"]))

    print(random.choice(("1", "2", "3", "4")))

    # random.shuffle() 是将一个列表中的元素打乱

    lists = [1, 2, 3, 4, 5, 6, 7, 8, 9]

    random.shuffle(lists)

    print(lists)

    # random.sample()是从指定序列中随机获取指定长度的片断

    listss = [i ** 3 for i in range(10)]

    print(listss)

    print(random.sample(listss, 3))

    print(listss)  # 原有list不变