三级菜单练习

 1 ‘‘‘
 2 实现行政区划三级菜单
 3 1. 每级菜单进入后显示所有选项
 4 2. 输入某个选项进入下一级菜单
 5    输错提示输错，重新输入
 6    输入Q退出程序
 7    输入B返回上一层
 8 ‘‘‘
 9 
10 import json
11 
12 file_path = ‘/Users/Rex/PycharmProjects/pyexe/Day1/admin_divisions.json‘
13 admin_div = {}
14 prov_list = []
15 with open (file_path) as f_obj:
16     admin_div = json.load(f_obj)
17 
18 num_pro = len(admin_div) #省个数
19 prov_list = list(admin_div.keys()) #省列表
20 
21 while 1:
22     # 输出省列表
23     print("**********行政区划***********")
24     for i in range(num_pro):
25         print(prov_list[i])
26     prov = input("输入你想查看的省(退出程序请输入Q+Enter)：")
27     if(prov == "Q"):
28         exit(0)
29     else:
30         try:
31             city_list = list(admin_div[prov])
32         except KeyError:
33             print("你输入的省不存在.")
34             continue
35         else:
36             while 1:
37                 #输出市列表
38                 print(‘**********行政区划-{p}***********‘.format(p = prov))
39                 num_city = len(city_list)
40                 for i in range(num_city):
41                     print(city_list[i])
42                 city = input("输入你想查看的市(退出程序请输入Q+Enter.返回上一层请输入B+Enter.)：")
43                 if (city == "Q"):
44                     exit(0)
45                 elif(city == ‘B‘):
46                     break
47                 else:
48                     try:
49                         county_list = admin_div[prov][city]
50                     except KeyError:
51                         print("你输入的市不存在.")
52                         continue
53                     else:
54                         #输出县列表
55                         print(‘**********行政区划-{c}***********‘.format(c=city))
56                         num_county = len(county_list)
57                         for i in range(num_county):
58                             print(county_list[i])
59                         while 1:
60                             nextstep = input("退出请输入Q+Enter.返回上一层请输入B+Enter.")
61                             if (nextstep == ‘B‘):
62                                 break
63                             elif (nextstep == ‘Q‘):
64                                 exit(0)
65                             else:
66                                 continue