我有这个代码
import json
from pprint import pprint
json_data=open('bookmarks.json')
jdata = json.load(json_data)
pprint (jdata)
json_data.close()
我怎样才能通过它搜索u'uri': u'http:？
问问题
116666 次
5 回答
34
ObjectPath是一个库，提供查询 JSON 以及字典和列表的嵌套结构的能力。例如，您可以搜索所有名为“foo”的属性，无论它们有多深，都可以使用$..foo.
虽然文档侧重于命令行界面，但您可以使用包的 Python 内部结构以编程方式执行查询。下面的示例假设您已经将数据加载到 Python 数据结构（字典和列表）中。如果您从 JSON 文件或字符串开始，您只需要先使用load或loads从json 模块开始。
import objectpath
data = [
{'foo': 1, 'bar': 'a'},
{'foo': 2, 'bar': 'b'},
{'NoFooHere': 2, 'bar': 'c'},
{'foo': 3, 'bar': 'd'},
]
tree_obj = objectpath.Tree(data)
tuple(tree_obj.execute('$..foo'))
# returns: (1, 2, 3)
请注意，它只是跳过了缺少“foo”属性的元素，例如列表中的第三项。您还可以执行更复杂的查询，这使得 ObjectPath 对于深度嵌套的结构非常方便（例如，查找 x 有 y 的位置有 z: $.x.y.z）。我建议您参阅文档和教程以获取更多信息。
于 2017-01-05T23:40:59.310 回答
28
由于json.loads简单地返回一个字典，您可以使用适用于字典的运算符：
>>> jdata = json.load('{"uri": "http:", "foo", "bar"}')
>>> 'uri' in jdata # Check if 'uri' is in jdata's keys
True
>>> jdata['uri'] # Will return the value belonging to the key 'uri'
u'http:'
编辑：要给出有关如何循环数据的想法，请考虑以下示例：
>>> import json
>>> jdata = json.loads(open ('bookmarks.json').read())
>>> for c in jdata['children'][0]['children']:
... print 'Title: {}, URI: {}'.format(c.get('title', 'No title'),
c.get('uri', 'No uri'))
...
Title: Recently Bookmarked, URI: place:folder=BOOKMARKS_MENU(...)
Title: Recent Tags, URI: place:sort=14&type=6&maxResults=10&queryType=1
Title: , URI: No uri
Title: Mozilla Firefox, URI: No uri
检查jdata数据结构将允许您根据需要导航它。您已经接到的pprint电话是一个很好的起点。
Edit2：另一个尝试。这将获取您在字典列表中提到的文件。有了这个，我认为你应该能够适应你的需要。
>>> def build_structure(data, d=[]):
... if 'children' in data:
... for c in data['children']:
... d.append({'title': c.get('title', 'No title'),
... 'uri': c.get('uri', None)})
... build_structure(c, d)
... return d
...
>>> pprint.pprint(build_structure(jdata))
[{'title': u'Bookmarks Menu', 'uri': None},
{'title': u'Recently Bookmarked',
'uri': u'place:folder=BOOKMARKS_MENU&folder=UNFILED_BOOKMARKS&(...)'},
{'title': u'Recent Tags',
'uri': u'place:sort=14&type=6&maxResults=10&queryType=1'},
{'title': u'', 'uri': None},
{'title': u'Mozilla Firefox', 'uri': None},
{'title': u'Help and Tutorials',
'uri': u'http://www.mozilla.com/en-US/firefox/help/'},
(...)
}]
然后“通过它搜索u'uri': u'http:'”，请执行以下操作：
for c in build_structure(jdata):
if c['uri'].startswith('http:'):
print 'Started with http'
于 2011-12-05T11:35:17.177 回答
1
jro 提供的 JSON 字典中似乎有一个错字（缺少冒号）。
正确的语法是：
jdata = json.load('{"uri": "http:", "foo": "bar"}')
在玩代码时，这为我清除了它。
于 2017-04-02T18:20:22.753 回答
0
用于搜索和打印 dicts 的函数，例如 JSON。*在python 3中制作
搜索：
def pretty_search(dict_or_list, key_to_search, search_for_first_only=False):
"""
Give it a dict or a list of dicts and a dict key (to get values of),
it will search through it and all containing dicts and arrays
for all values of dict key you gave, and will return you set of them
unless you wont specify search_for_first_only=True
:param dict_or_list:
:param key_to_search:
:param search_for_first_only:
:return:
"""
search_result = set()
if isinstance(dict_or_list, dict):
for key in dict_or_list:
key_value = dict_or_list[key]
if key == key_to_search:
if search_for_first_only:
return key_value
else:
search_result.add(key_value)
if isinstance(key_value, dict) or isinstance(key_value, list) or isinstance(key_value, set):
_search_result = pretty_search(key_value, key_to_search, search_for_first_only)
if _search_result and search_for_first_only:
return _search_result
elif _search_result:
for result in _search_result:
search_result.add(result)
elif isinstance(dict_or_list, list) or isinstance(dict_or_list, set):
for element in dict_or_list:
if isinstance(element, list) or isinstance(element, set) or isinstance(element, dict):
_search_result = pretty_search(element, key_to_search, search_result)
if _search_result and search_for_first_only:
return _search_result
elif _search_result:
for result in _search_result:
search_result.add(result)
return search_result if search_result else None
打印：
def pretty_print(dict_or_list, print_spaces=0):
"""
Give it a dict key (to get values of),
it will return you a pretty for print version
of a dict or a list of dicts you gave.
:param dict_or_list:
:param print_spaces:
:return:
"""
pretty_text = ""
if isinstance(dict_or_list, dict):
for key in dict_or_list:
key_value = dict_or_list[key]
if isinstance(key_value, dict):
key_value = pretty_print(key_value, print_spaces + 1)
pretty_text += "\t" * print_spaces + "{}:\n{}\n".format(key, key_value)
elif isinstance(key_value, list) or isinstance(key_value, set):
pretty_text += "\t" * print_spaces + "{}:\n".format(key)
for element in key_value:
if isinstance(element, dict) or isinstance(element, list) or isinstance(element, set):
pretty_text += pretty_print(element, print_spaces + 1)
else:
pretty_text += "\t" * (print_spaces + 1) + "{}\n".format(element)
else:
pretty_text += "\t" * print_spaces + "{}: {}\n".format(key, key_value)
elif isinstance(dict_or_list, list) or isinstance(dict_or_list, set):
for element in dict_or_list:
if isinstance(element, dict) or isinstance(element, list) or isinstance(element, set):
pretty_text += pretty_print(element, print_spaces + 1)
else:
pretty_text += "\t" * print_spaces + "{}\n".format(element)
else:
pretty_text += str(dict_or_list)
if print_spaces == 0:
print(pretty_text)
return pretty_text
于 2017-06-08T21:52:36.563 回答
-1
如果您只需要输出（并且更熟悉命令行），则可以使用jsonpipe ：
cat bookmarks.json | jsonpipe |grep uri
于 2011-12-05T11:52:33.580 回答