Question

我正在尝试解析reddit JSON文件以获取帖子的标题，但是当我使用此代码时：

import urllib2
import json

response = urllib2.urlopen('http://www.reddit.com/r/technology/.json')
data = json.load(response)   
print data['title']

我收到此错误：

Traceback (most recent call last):
  File "C:\Users\Harry\Desktop\py\jason.py", line 6, in <module>
    print data['title']
KeyError: 'title'

任何帮助都将不胜感激，谢谢。

Answer 1

该回复没有'title'顶级密钥。在顶级词典中只能找到'kind'和'data'个键。

你需要仔细观察这里的结构; data键包含实际的有效负载，但这也是没有'title'键的字典。

以下是内容的删除版本：

>>> import pprint
>>> pprint.pprint(data)
{u'data': {u'after': u't3_1wnfuv',
           u'before': None,
           u'children': [{u'data': {u'approved_by': None,
                                    u'author': u'papa00king',
                                    # [...]
                                    # Many keys omitted
                                    # [...]
                                    u'title': u'UK government will unblock websites after adult filter blunder',
                                    u'ups': 1030,
                                    u'url': u'http://www.engadget.com/2014/01/31/uk-government-adult-filter-whitelist/',
                                    u'visited': False},
                          u'kind': u't3'},
                          # [...]
                          # Many many more children
                          # [...]
                          ],
           u'modhash': u''},
 u'kind': u'Listing'}

如果您要查找结果中所有孩子的头衔，请使用：

for child in data['data']['children']:
    print child['data']['title']

换句话说，每个“对象”都有kind和data个键，而Listing种对象都有一个children键，一个列表包含kind和data个键的更多对象。您要查找的t3种对象在title结构中包含data个键。

演示：

>>> for child in data['data']['children']:
...     print child['data']['title']
... 
UK government will unblock websites after adult filter blunder
The upside to being let go by Nokia - Thousands of workers made redundant have set up over 400 new technology companies using grants of up to €20,000 - costing Nokia 'tens of millions of Euro's'
You wouldn't download a car: Honda releases concept car 3D printing files
Could 3D printing provide new solutions for disabled people? - Disabled people often need personalised equipment to help with their individual needs. Could 3D printing provide a cheap and efficient solution?
Five of India's most popular small cars fail their first ever crash tests, showing that they could lead to fatalities or serious injuries if involved in an accident.
Kansas Legislature Wants To Stop Any Other Kansas Cities From Getting Google Fiber
Google’s Latest Moves Toward Scarily Personalized Searches
This $75 synthesizer will turn anything into an instrument
Best Buy slashes price of Surface Pro by $400
This Is What a Computer Sees When It Watches The Matrix
Windows 8.1 update to hide tile interface by default
Young farmers win award for designing cattle management app
IBM's speedy graphene chip could lead to super-efficient mobile devices
South Korea fines Google $196K for illegal data gathering
Microsoft said to be preparing to promote from within, make Satya Nadella next CEO
Pirate Bay ban lifted in Netherlands as blocking torrent sites ruled ‘ineffective’
Haptics, Trackballs and Cheeto Dust: How Valve built the game controller of the future
Icelandic drilling project opens door to volcano-powered electricity
Here's how to know if your Gmail account has been hacked
Amazon considering $20 to $40 price hike for Prime service in US
Massive spending on computing gear underpins Google profits
Yahoo Mail accounts breached, number of affected users not disclosed
AMD (almost) rolls out Mantle, its high performance alternative to Direct3D and OpenGL
Physicists create synthetic magnetic monopole predicted more than 80 years ago
Facebook Is About To Let You Go Anonymous For The First Time

在python中解析JSON时出错

1 个答案: