Python学习-------------------三级菜单简单版

题目：

多级菜单
         1.三级菜单
         2.可依次选择进入的各子菜单
         3.所需新知识点：列表、字典

ReadMe：

             这个做循环，比较绕脑子

             点开运行即可

Mind Map：

代码：

#!/usr/bin/env python
#py3.5
#2018.02.06
#-*- Coding:utf-8 -*-
# Author:Eric.Shen
#多级菜单
#1.三级菜单
#2.可依次选择进入的各子菜单
#3.所需新知识点：列表、字典

#自己建立一个三级字典
menu = {
    "衣服":{
        "男士":["上衣","下衣","鞋包","皮带"],"女士":["上衣","裤子","裙子","鞋包"],"儿童":["上衣","下衣","鞋包"]},
    "汽车":{
        "精品车":["宝马","奔驰","路虎"],"二手车":["大众","本田","荣威"]},
    "食物":{"肉":["肥肉","瘦肉","肥瘦"]}
}

#将三级菜单的key赋值product_list
product_list = list(menu.keys())#获得一级菜单
while True:
    print("菜单".center(50,"*"))
    for line in product_list:
        print(product_list.index(line),line)
    print("------------------")
    choice = input("请输入编号或者输入q退出b返回：")
    if choice.isdigit():
        choice = int(choice)
        if choice >= 0 and choice < len(product_list):
            choice_name = product_list[choice]#获得第一级Id
            product = list(menu[choice_name].keys())#获得选择商品的下一级菜单
            while True:
                print("商品".center(50,"*"))
                for line2 in product:#打印二级菜单
                    print(product.index(line2),line2)
                print("----------------")
                choice_product = input("请输入编号或者输入q退出b返回：")
                if choice_product.isdigit():
                    choice_product = int(choice_product)
                    if choice_product >= 0 and choice_product < len(product_list):
                        choice_name2 = product[choice_product]#获得第二级的Id
                        choice_name2_list = menu[choice_name][choice_name2]#获得第二级菜单
                        while True:
                            print("衣物".center(50,"*"))
                            for line3 in  choice_name2_list:
                                print(choice_name2_list.index(line3),line3)
                            back_or_quit = input("返回输入b，退出输入q")
                            if back_or_quit == "b":
                                break
                            elif back_or_quit == "q":
                                exit()
                            else:
                                print("输入错误！")
                    else:
                        print("输入%d不存在"%(choice_product))
                elif choice_product == "q":
                    exit()
                elif choice_product == "b":
                    break
                else:
                    print("输入非法！")
        else:
            print("输入%d不存在"%(choice))
    elif choice == "q":
        exit()
    elif choice == "b":
        break
    else:
        print("输入非法！")

欢迎指错