json的运用

# coding:utf-8

在python中发送请求

下载requests包，使用requests发请求

windows+r 输入cmd 回车打开命令行工具 输入pip install requests

输入pip list 查看已经安装过的包

import requests

# python内置的包，json
import json
while True:



print '**************欢迎使用天气查询系统*****************'
# 输入一个要查询的城市名称
city = raw_input('请输入要查询的城市名称(输入q退出)：')
if city == 'q':
    break
# 1.准备url地址
url = 'http://api.map.baidu.com/telematics/v3/weather?location=%s&output=json&ak=TueGDhCvwI6fOrQnLM0qmXxY9N0OkOiQ&callback=?'%city

# 2.发送一个get请求，获取url地址下的资源内容
# get(url) 需要将url地址作为参数进行传递
# response 接受服务器返回的响应数据
response = requests.get(url)
# 把json字符串转换python中的字典或列表
weather_dict = json.loads(response.content)
# 根据key取出字典中对应的值
date = weather_dict.get('date')

# 取出results列表
results = weather_dict['results']
# 取出results中的字典
detail_dict = results[0]
# 取出当前城市
current_city = detail_dict['currentCity']
print u'当前城市：%s' % current_city
# 取出pm值
pm25 = detail_dict['pm25']
# 把取出的pm25字符串转换为数字，再进行比较
pm25 = int(pm25)
if pm25 <= 50:
    print 'pm值%s，优' % pm25
elif pm25 <= 100:
    print 'pm值%s，良' % pm25
elif pm25 <= 150:
    print 'pm值%s，轻度污染' % pm25
elif pm25 <= 200:
    print 'pm值%s，中度污染' % pm25
elif pm25 <= 300:
    print 'pm值%s，重度污染' % pm25
else:
    print 'pm值%s，严重污染' % pm25

# 取出指引列表
indexs = detail_dict['index']
# for循环遍历index列表，取出小字典
for index in indexs:
    title = index['title']
    zs = index['zs']
    tipt = index['tipt']
    des = index['des']
    print u'标题：%s 指数：%s 提示：%s 建议：%s'%(title,zs,tipt,des)
# 取出天气情况列表
weather_data = detail_dict['weather_data']
# for循环遍历weather_data，取出小字典
for weather_dict in weather_data:
    date = weather_dict['date']
    weather = weather_dict['weather']
    wind = weather_dict['wind']
    temperature = weather_dict['temperature']
    print u'日期：%s 天气：%s 风级：%s 温度：%s'%(date,weather,wind,temperature)