三级菜单(4) 函数优化

函数优化

# -*- coding: utf-8 -*-# @Author: oppend# @Date:   2017-07-31 21:00:25# @Last Modified by:   oppend# @Last Modified time: 2017-08-02 22:08:46# 三级菜单,省市县,增删改查def write_file(old,new):    with open('data','w') as write_file:        write_file.write(str(parrent_layer[0]).replace(old,new))        write_file.flush()parrent_layer = {}with open('data','r') as read_file:    menu = eval(read_file.read().strip())    current_layer = menu    layer_num = 0    while True:        for province in current_layer:            print(province)        choice = input('[b]上级[a]增加[d]删除[e]修改[q]退出:')        if choice in current_layer:            parrent_layer[layer_num] = current_layer            layer_num += 1            current_layer = current_layer[choice]        elif choice == 'b':            if parrent_layer:                layer_num -= 1                current_layer = parrent_layer.pop(layer_num)            else:                print('已经是最上级')        elif choice == 'a':            add_choice = input('增加:')              before = str(current_layer)            current_layer[add_choice] = {}            after = str(current_layer)            write_file(before,after)        elif choice == 'd':            del_choice = input('删除:')            before = str(current_layer)            if del_choice in current_layer:                del current_layer[del_choice]                after = str(current_layer)                write_file(before,after)            else:                print('无法删除不存在键')        elif choice == 'e':            # 修改            before = input('修改:')            after = input('改为:')            current_layer[after] = current_layer.pop(before)            write_file(before,after)        elif choice == 'q':            break        else:            print('不存在')