Python之三层菜单

三层菜单，根据用户所选数字，进入子菜单。一级一级呈现。

menu = {
    'Beijing': {
        "ChaoYang": {
            "CBD": ['CICC', 'CCTV'],
            "JinRongJie": ["CT"],
            "Wangjing": ["Momo", "ChuiZI"]
        },
        "HaiDian": ['Baidu', 'Youku']
    },
    'Shanghai': {
        "PuDong": ["Ctrip", "One Shop"],
        "PuXi": ["China Bank", "America Bank"]
    }
}
exit_flag = False
while not exit_flag:
    for index, key in enumerate(menu.keys()):
        print(index, key)
    choice_1 = input("Please choose menu to enter:").strip()
    if choice_1.isdigit():
        choice_1 = int(choice_1)

        key_1 = list(menu.keys())[choice_1]
        while not exit_flag:
            for index, key in enumerate(menu[key_1]):
                print('-->', index, key)
            choice_2 = input("Please choose menu to enter:").strip()
            if choice_2.isdigit():
                choice_2 = int(choice_2)

                key_2 = list(menu[key_1].keys())[choice_2]
                while not exit_flag:
                    for index, key in enumerate(menu[key_1][key_2]):
                        print('-->-->', index, key)
                    choice_3 = input("Please choose menu to enter:").strip()
                    if choice_3.isdigit():
                        print("This is the last level...")
                    elif choice_3 == 'quit':
                        exit_flag = True
                    elif choice_3 == 'back':
                        break
else:
    print("====Going to quit==== ")

 注：此版本为Python3.0版本