Python_简单三级菜单制作

一:制作要求

　　1.三级菜单
　　2.可依次选择进入各子菜单
　　3.所需新知识点:字典,列表

　　*本文通过三种方法完成,第一种:只使用循环,第二种:使用列表,第三种:使用字典

二:FlowChart流程图

　　流程图功能总体浏览流程图

功能流程图

与上图对应,实现方式图解:

while用来判断输入的数据和允许输入数据中的哪一项匹配,if来进行判断是否退出本次循环,

三:具体实现代码:

　　1.没有使用列表字典　

　　 
  1 #三级菜单 输入都是用一个变量   0120使用字典,列表
  2 
  3 #思路:while
  4 #定义一级菜单
  5 msg='''
  6 请输入你要进行的操作前面的索引(1,2,3,b):
  7     
  8     1.北京
  9     2.上海
 10     3.香港
 11     b.退出
 12 '''
 13 #定义二级菜单
 14 msg_1='''
 15     1.朝阳区
 16     2.西城区
 17     3.海淀区
 18     b.返回上一级
 19 '''
 20 msg_2_2='''
 21     1.西城区_A
 22     2.西城区_B
 23     3.西城区_C
 24     b.返回上一级
 25 '''
 26 #定义三级菜单
 27 msg_2_1='''
 28     1.朝阳区_A
 29     2.朝阳区_B
 30     3.朝阳区_C
 31     b.返回上一级
 32 '''
 33 while True:
 34     #输出一级菜单:
 35     print(msg)
 36     select_input=input("请输入你的选择:")
 37     #选项一
 38     while select_input== "1":
 39         print(msg_1)
 40         select_input_1 = input("请输入你的选择:")
 41         while select_input_1 == "1":
 42             print(msg_2_1)
 43             select_input_2 = input("请输入你的选择:")
 44             if select_input_2=="b":
 45                 break
 46         while select_input_1 == "2":
 47             print(msg_2_2)
 48             select_input_2 = input("请输入你的选择:")
 49             if select_input_2 == "b":
 50                 break
 51         while select_input_1 == "3":
 52             print(msg_2_2)
 53             select_input_2 = input("请输入你的选择:")
 54             if select_input_2 == "b":
 55                 break
 56         if select_input_1== "b":
 57             break
 58     #选项二
 59     while select_input == "2":
 60         print(msg_1)
 61         select_input_1 = input("请输入你的选择:")
 62         while select_input_1 == "1":
 63             print(msg_2_1)
 64             select_input_2 = input("请输入你的选择:")
 65             if select_input_2 == "b":
 66                 break
 67         while select_input_1 == "2":
 68             print(msg_2_2)
 69             select_input_2 = input("请输入你的选择:")
 70             if select_input_2 == "b":
 71                 break
 72         while select_input_1 == "3":
 73             print(msg_2_2)
 74             select_input_2 = input("请输入你的选择:")
 75             if select_input_2 == "b":
 76                 break
 77         if select_input_1 == "b":
 78             break
 79     #选项三
 80     while select_input == "3":
 81         print(msg_1)
 82         select_input_1 = input("请输入你的选择:")
 83         while select_input_1 == 1:
 84             print(msg_2_1)
 85             select_input_2 = input("请输入你的选择:")
 86             if select_input_2 == "b":
 87                 break
 88         while select_input_1 == "2":
 89             print(msg_2_2)
 90             select_input_2 = input("请输入你的选择:")
 91             if select_input_2 == "b":
 92                 break
 93         while select_input_1 == "3":
 94             print(msg_2_2)
 95             select_input_2 = input("请输入你的选择:")
 96             if select_input_2 == "b":
 97                 break
 98         if select_input_1 == "b":
 99             break
100     #选项四
101     if select_input=="b":
102         break
103 print("本次使用结束!")
View Code　　

　　2.使用列表　

　　 
 1 # 三级菜单 输入都是用一个变量   0120使用字典,列表
 2 
 3 # 思路:while
 4 # 通过定义列表进行选项存储
 5 list=["北京","上海","香港","退出"]
 6 list_1=["朝阳区","西城区","海淀区","返回上一级"]
 7 list_1_1=["朝阳区_A","朝阳区_B","朝阳区_C","返回上一级"]
 8 list_1_2=["西城区_A","西城区_B","西城区_C","返回上一级"]
 9 while True:
10     # 输出一级菜单:
11     for i in list:
12         print(" \n%s: %s"%(list.index(i)+1,i))
13     select_input = input("请输入你的选择:")
14     # 选项一
15     while select_input == "1":
16         for i in list_1:
17             print(" \n%s: %s" % (list_1.index(i) + 1, i))
18         select_input_1 = input("请输入你的选择:")
19         while select_input_1 == "1":
20             for i in list_1_1:
21                 print(" \n%s: %s" % (list_1_1.index(i) + 1, i))
22             select_input_2 = input("请输入你的选择:")
23             if select_input_2 == "4":
24                 break
25         while select_input_1 == "2":
26             for i in list_1_2:
27                 print(" \n%s: %s" % (list_1_2.index(i) + 1, i))
28             select_input_2 = input("请输入你的选择:")
29             if select_input_2 == "4":
30                 break
31         while select_input_1 == "3":
32             for i in list_1_2:
33                 print(" \n%s: %s" % (list_1_2.index(i) + 1, i))
34             select_input_2 = input("请输入你的选择:")
35             if select_input_2 == "4":
36                 break
37         if select_input_1 == "4":
38             break
39     # 选项二
40     while select_input == "2":
41         for i in list_1:
42             print(" \n%s: %s" % (list_1.index(i) + 1, i))
43         select_input_1 = input("请输入你的选择:")
44         while select_input_1 == "1":
45             for i in list_1_2:
46                 print(" \n%s: %s" % (list_1_2.index(i) + 1, i))
47             select_input_2 = input("请输入你的选择:")
48             if select_input_2 == "4":
49                 break
50         while select_input_1 == "2":
51             for i in list_1_2:
52                 print(" \n%s: %s" % (list_1_2.index(i) + 1, i))
53             select_input_2 = input("请输入你的选择:")
54             if select_input_2 == "4":
55                 break
56         while select_input_1 == "3":
57             for i in list_1_2:
58                 print(" \n%s: %s" % (list_1_2.index(i) + 1, i))
59             select_input_2 = input("请输入你的选择:")
60             if select_input_2 == "4":
61                 break
62         if select_input_1 == "4":
63             break
64     # 选项三
65     while select_input == "3":
66         for i in list_1:
67             print(" \n%s: %s" % (list_1.index(i) + 1, i))
68         select_input_1 = input("请输入你的选择:")
69         while select_input_1 == 1:
70             for i in list_1_2:
71                 print(" \n%s: %s" % (list_1_2.index(i) + 1, i))
72             select_input_2 = input("请输入你的选择:")
73             if select_input_2 == "4":
74                 break
75         while select_input_1 == "2":
76             for i in list_1_2:
77                 print(" \n%s: %s" % (list_1_2.index(i) + 1, i))
78             select_input_2 = input("请输入你的选择:")
79             if select_input_2 == "4":
80                 break
81         while select_input_1 == "3":
82             for i in list_1_2:
83                 print(" \n%s: %s" % (list_1_2.index(i) + 1, i))
84             select_input_2 = input("请输入你的选择:")
85             if select_input_2 == "4":
86                 break
87         if select_input_1 == "4":
88             break
89     # 选项四
90     if select_input == "4":
91         break
92 print("本次使用结束!")
View Code
使用列表运行效果和第一种方法类似,只不过把返回的值改成了4,

　　3.使用字典

　　 
# 三级菜单 输入都是用一个变量   0120使用字典,列表

# 思路:while
# 通过字典进行选项存储
dic={
    "1.北京":{
        "1.朝阳区":["朝阳区_A","朝阳区_B","朝阳区_C","返回上一级"],
        "2.西城区":["西城区_A","西城区_B","西城区_C","返回上一级"],
        "3.海淀区":[],
        "4.返回上一级":[]
    },
    "2.上海":{},
    "3.香港":{},
    "b.退出":{}
}

while True:
    # 输出一级菜单:
    print(dic.keys())
    select_input = input("请输入你的选择:")
    # 选项一
    while select_input == "1":
        print(dic["1.北京"].keys())
        select_input_1 = input("请输入你的选择:")
        while select_input_1 == "1":
            print(dic["1.北京"]["1.朝阳区"])
            select_input_2 = input("请输入你的选择:")
            if select_input_2 == "b":
                break
        while select_input_1 == "2":
            print(dic["1.北京"]["1.朝阳区"])
            select_input_2 = input("请输入你的选择:")
            if select_input_2 == "b":
                break
        while select_input_1 == "3":
            print(dic["1.北京"]["1.朝阳区"])
            select_input_2 = input("请输入你的选择:")
            if select_input_2 == "b":
                break
        if select_input_1 == "b":
            break
    # 选项二
    while select_input == "2":
        print(dic["1.北京"].keys)
        select_input_1 = input("请输入你的选择:")
        while select_input_1 == "1":
            print(dic["1.北京"]["1.朝阳区"])
            select_input_2 = input("请输入你的选择:")
            if select_input_2 == "b":
                break
        while select_input_1 == "2":
            print(dic["1.北京"]["1.朝阳区"])
            select_input_2 = input("请输入你的选择:")
            if select_input_2 == "b":
                break
        while select_input_1 == "3":
            print(dic["1.北京"]["1.朝阳区"])
            select_input_2 = input("请输入你的选择:")
            if select_input_2 == "b":
                break
        if select_input_1 == "b":
            break
    # 选项三
    while select_input == "3":
        print(dic["1.北京"].keys)
        select_input_1 = input("请输入你的选择:")
        while select_input_1 == 1:
            print(dic["1.北京"]["1.朝阳区"])
            select_input_2 = input("请输入你的选择:")
            if select_input_2 == "b":
                break
        while select_input_1 == "2":
            print(dic["1.北京"]["1.朝阳区"])
            select_input_2 = input("请输入你的选择:")
            if select_input_2 == "b":
                break
        while select_input_1 == "3":
            print(dic["1.北京"]["1.朝阳区"])
            select_input_2 = input("请输入你的选择:")
            if select_input_2 == "b":
                break
        if select_input_1 == "b":
            break
    # 选项四
    if select_input == "b":
        break
print("本次使用结束!")
View Code

四:运行效果截图(第一种方法):

 

 



五:注意事项


　　1.Python虽然简单,但是一定要熟练掌握格式,有的时候差一个空格都会出错而且还不容易排除错误.
　　2.关于语句:
　　　　select_input=b 
　　　　while int(select_input)==1 
　　　　运行报错:ValueError: invalid literal for int() with base 10: 'b',
　　　　语法错误
　　　　出错原因:Python3.0以后的版本不能进行字符串转换类型之后与数字之间的比较与判断
　　　　所以改成:select_input=="1"



 






            

            
posted @ 
2018-01-20 15:11 
爱华顿g 
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