一、練習(xí)要求

• 從網(wǎng)上找到中國省市區(qū)的json或字典數(shù)據(jù)
• 一、二、三級菜單分別對應(yīng)省市區(qū)，且每個都有單獨(dú)的代碼
• 省、市菜單有輸入對應(yīng)代碼進(jìn)入下一級功能
• 有返回上一級功能和退出機(jī)制

二、練習(xí)分析

2.1 獲取源數(shù)據(jù)

1. 全國省市區(qū)json——來源于csdb，復(fù)制數(shù)據(jù)并另存為json格式。（最好在復(fù)制后去在線json檢測網(wǎng)站檢查是否valid）

2. 最新縣及縣以上行政區(qū)劃代碼——來源于統(tǒng)計局，復(fù)制成文本格式，后期再通過python來解析txt獲取并組成{（代碼，省）：{（代碼，市）：{（代碼，區(qū)）}}}

3. 直接通過統(tǒng)計局的網(wǎng)站，通過抓取來生成json文件（這個麻煩一些）

2.2 步驟分析

1. 用函數(shù)來實(shí)現(xiàn)模塊很方便，新手練習(xí)還是逐層實(shí)現(xiàn)
2. 進(jìn)入程序，顯示省的名字和對應(yīng)數(shù)字列表，以三列的形式來顯示
3. 提示輸入省級代碼，輸入正確則進(jìn)入對應(yīng)市級列表；輸入非法則提示重新輸入；提示輸入‘q’來退出程序（用break循環(huán)）
4. 市級進(jìn)到縣級同上；另外，提示輸入‘r’來返回上一級
5. 縣級界面，提示輸入‘r’來返回上一級，‘q’來退出程序
6. 設(shè)立標(biāo)志位，整體用while來循環(huán)

三、代碼實(shí)現(xiàn)

• 以json方法來實(shí)現(xiàn)最為快捷
• json文件命名為“City_json.json ”

• 下面是版本一：

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

'''China province to city, to district'''
__author__:'Wu HH'

# 導(dǎo)入json文件
import json
filename = 'City_json.json'
with open(filename, 'r') as file:
    china_data = json.load(file)

# 打印省級的函數(shù)
def print_pro():
    count = 0
    for i in range(len(china_data)):
        count += 1
        print(china_data[i]['name'].ljust(8,'>'),'%02d'.ljust(6,' ') % i, end='')
        # 用于打印成3列
        if count % 3 == 0:
            print('')

# 打印市級的函數(shù)
def print_city(city_num):
    count = 0
    for i in range(len(china_data[city_num]['city'])):
        count += 1
        print(china_data[city_num]['city'][i]['name'].ljust(8,'>'),'%02d'.ljust(6,' ') % i, end='')
        # 用于打印成3列
        if count % 3 == 0:
            print('')

# 打印縣級的函數(shù)
def print_area(city_num, area_num):
    count = 0
    for i in range(len(china_data[city_num]['city'][area_num]['area'])):
        count += 1
        print(china_data[city_num]['city'][area_num]['area'][i].ljust(8,'>'),'%02d'.ljust(6,' ') % i, end='')
        # 用于打印成3列
        if count % 3 == 0:
            print('')

# 定位標(biāo)志
loca_num = 0

while True:

    # 打印省級
    if loca_num == 0:
        print_pro()
        loca_num = 1

    if loca_num == 1:
        # 提示輸入省級編號進(jìn)入市級，并提示q退出
        into_city_num = input('Please input number to get into city. "q" to quit. ')
        if into_city_num == 'q':
            break
        elif int(into_city_num) > 0 and int(into_city_num) <= len(china_data):
            into_city_num = int(into_city_num)
            if loca_num == 1:
                print_city(into_city_num)
            loca_num = 2
        else:
            print('please input a valid number')

    if loca_num == 2:
        # 提示輸入市級編號進(jìn)入縣級，并提示q退出，r返回上一級
        into_area_num = input('Please input number to get into city. "q" to quit. "r" to return. ')
        if into_area_num == 'q':
            break
        elif into_area_num == 'r':
            loca_num = 0
            continue
        elif int(into_area_num) > 0 and int(into_area_num) <= len(china_data[into_city_num]['city']):
            into_area_num = int(into_area_num)
            if loca_num == 2:
                print_area(into_city_num, into_area_num)
            loca_num = 3
        else:
            print('please input a valid number')

    if loca_num == 3:
        # 提示q退出，r返回上一級
        input_in_area = input('"q" to quit. "r" to return. ')
        if input_in_area == 'q':
            break
        elif input_in_area == 'r':
            loca_num = 2
            print_city(into_city_num)
            continue
        else:
            print("please input a 'q' or 'r'")

• 下面是優(yōu)化版本二：（網(wǎng)上找的博客園-金角大王）

• 很佩服這個版本，但是交互是通過輸入完成城市名而不是數(shù)字

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

'''more elegent version of China province program'''
__author__:'Wu HH'

# 導(dǎo)入json文件
import json
filename = 'City_json.json'
with open(filename, 'r') as file:
    china_data = json.load(file)

# 重組json成層疊字典{a:{b1:{c1:[]},c2:{}},b2:{...}...}
china_data_dic = {}
for province_total in china_data:
    city_temp = {}
    for city_total in province_total['city']:
        city_temp[city_total['name']] = city_total['area']
    china_data_dic[province_total['name']] = city_temp


exit_active = False

current_class = china_data_dic
parent_classes = [china_data_dic]

while not exit_active:
    count_num = 0
    for k in current_class:
        count_num += 1
        print(k.ljust(8, ' '),end='')
        if count_num % 3 == 0:
            print('')
    choice = input(">>:").strip()
    if choice == 'b' and parent_classes != []:
        current_class = parent_classes[-1]
        parent_classes.pop()
    elif choice == 'q':
        exit_active = True
    elif choice not in current_class:
        continue
    else:
        if current_class not in parent_classes:
            parent_classes.append(current_class)
        try:
            current_class = current_class[choice]
        except TypeError:
            continue

思考了好一會兒都沒想到怎么解決“縣級在非合法輸入后，需要‘b’兩次才能返回市級”的bug。先留著，以后有空繼續(xù)思考