在 Python 中更新和创建多维字典
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Update and create a multi-dimensional dictionary in Python
提问by gregwhitworth
I am parsing JSON that stores various code snippets and I am first building a dictionary of languages used by these snippets:
我正在解析存储各种代码片段的 JSON，我首先构建了这些片段使用的语言字典：
snippets = {'python': {}, 'text': {}, 'php': {}, 'js': {}}
Then when looping through the JSON I'm wanting add the information about the snippet into its own dictionary to the dictionary listed above. For example, if I had a JS snippet - the end result would be:
然后，当循环遍历 JSON 时，我想将有关片段的信息添加到其自己的字典中，以添加到上面列出的字典中。例如，如果我有一个 JS 片段 - 最终结果将是：
snippets = {'js':
{"title":"Script 1","code":"code here", "id":"123456"}
{"title":"Script 2","code":"code here", "id":"123457"}
}
Not to muddy the waters - but in PHP working on a multi-dimensional array I would just do the following (I am lookng for something similiar):
不要搅浑水 - 但在处理多维数组的 PHP 中，我只会执行以下操作（我正在寻找类似的东西）：
snippets['js'][] = array here
I know I saw one or two people talking about how to create a multidimensional dictionary - but can't seem to track down adding a dictionary to a dictionary within python. Thanks for the help.
我知道我看到一两个人在谈论如何创建多维字典 - 但似乎无法追踪在 python 中将字典添加到字典中。谢谢您的帮助。
采纳答案by JBernardo
This is called autovivification:
这称为自动活化：
You can do it with defaultdict
你可以用 defaultdict
def tree():
return collections.defaultdict(tree)
d = tree()
d['js']['title'] = 'Script1'
If the idea is to have lists, you can do:
如果想法是有列表，你可以这样做：
d = collections.defaultdict(list)
d['js'].append({'foo': 'bar'})
d['js'].append({'other': 'thing'})
The idea for defaultdict it to create automatically the element when the key is accessed. BTW, for this simple case, you can simply do:
defaultdict 的想法是在访问键时自动创建元素。顺便说一句，对于这个简单的情况，您可以简单地执行以下操作：
d = {}
d['js'] = [{'foo': 'bar'}, {'other': 'thing'}]
回答by placeybordeaux
From
从
snippets = {'js':
{"title":"Script 1","code":"code here", "id":"123456"}
{"title":"Script 2","code":"code here", "id":"123457"}
}
It looks to me like you want to have a list of dictionaries. Here is some python code that should hopefully result in what you want
在我看来，您想要一个字典列表。这是一些 python 代码，希望能产生你想要的结果
snippets = {'python': [], 'text': [], 'php': [], 'js': []}
snippets['js'].append({"title":"Script 1","code":"code here", "id":"123456"})
snippets['js'].append({"title":"Script 1","code":"code here", "id":"123457"})
print(snippets['js']) #[{'code': 'code here', 'id': '123456', 'title': 'Script 1'}, {'code': 'code here', 'id': '123457', 'title': 'Script 1'}]
Does that make it clear?
这样说清楚了吗？
