# 含多空格字符串的分割

hello = "hello python hello"

print(a.split(" ")) # ['hello', 'python', '', 'hello']

print(hello.split())  # ['hello', 'python', 'hello']

print(len(a.split(" ")[2])) # ''也是一个字符串类型数据，只是什么都没有 # 0

print(a.split(" ")[2]) # 没有任何内容

print(type(a.split(" ")[2])) # <class 'str'> 字符串类型

# 字符串定义

hello = """hello python""" # hello python

hell0 = ""hello python"" # SyntaxError: invalid syntax

list1 = [10,3.13,'hello',True]

list1.append(3)

print(list1)

list1[2] = '你好'

print(list1)

list1.remove('你好')

print(list1)

# list1.remove('nihao') # ValueError: list.remove(x): x not in list

list1.pop(-2)

print(list1)

# 关于del的两种删除方式

del list1[0]

print(list1)

del(list1[0])

print(list1)

#关于while的break

内循环里执行 break 不会导致外循环一起结束

j = 0

while j < 3:

print("外层运行中")

i = 0

while i < 6:

if i ==4:

break

print("内层运行中")

i += 1

if j ==2:

break

j += 1

名片管理系统

1 while True: 2     print("欢迎使用ITV1.0") 3     active = True 4     while True: 5         if active: 6             name = input("请输入姓名：(按q退出）") 7             if name == 'q': 8                 break 9             length_name = len(name)10             if (length_name < 6) or (length_name > 20):11                 print("长度错误")12                 continue13             else:14                 pass15             while True:16                 if active:17                     tel = input("请输入手机号：(按q返回上一级）")18                     if tel == 'q':19                         break20                     length_tel = len(tel)21                     if length_tel != 11:22                         print("长度不合法")23                         continue24                     else:25                         pass26                     while True:27                         sex = input("请输入性别：(按q返回上一级）")28                         if sex == 'q':29                             break30                         if sex == '男' or sex == '女':31                             print("录入成功")32                             active = False33                         else:34                             print("性别错误")35                             continue36                         print("*" * 5 + "名片信息" + "*" * 5)37                         print("姓名：%s" % name)38                         print("手机号: %s" % tel)39                         print("性别：%s" % sex)40                         break41                 else:42                     break43         else:44             break45     ask = input("是否继续录入信息？y/n")46     if ask == 'n':47         print("谢谢使用V1.0")48         break