python字符串怎么转换成字典_用python将字符串转换成字典

I know that this question sound a duplicate, but it's not, at least looked for a while and I couldn't fine nothing for my specific problem.

I have the following string:

"{first : {name : 'test', value : 100}, second : {name : 'test2', value : 50}}"

And I want to convert that string to a dictionary something like this:

{'first': {'name': 'test', 'value' : 100}, 'second': {'name': 'test2', 'value' : 50}}

Any ideas? I'm working with Python 2.5

Thanks

解决方案

First, if you're generating these strings from dictionaries (in Python or almost any other language), you might want to consider generating them in a way that can be easily parse. For example, in Python. either repr(d) or json.dumps(d) will give you something very similar to your existing string, but with proper quotes.

But if you've just got a mess of strings someone else gave you, the easiest thing to do might be to regex it into an actual JSON string so you can parse it:

json.loads(re.sub(r",\s*(\w+)", r", '\1'",

re.sub(r"\s*\{\s*(\w+)", r"{'\1'", x)).replace("'", '"'))

In 2.5, there's no built-in json module, so you probably want to pip install simplejson and then you can do this:

try:

import json

except ImportError:

import simplejson as json

(Or, of course, you can just require simplejson unconditionally, if you prefer.)

A different alternative is to use ast.literal_eval instead of json.loads. Which one is appropriate depends on more information about your strings. JSON is more restricted than Python syntax, so it's safer if you're worried about the source of your input, but not as flexible if your input might legitimately have stuff that JSON can't handle, like 1+3j.

However, like json, ast is new to 2.6, and there's no drop-in replacement available on PyPI. Fortunately, 2.5 does have the _ast module, and you can just copy and paste the source literal_eval from 2.6's ast.py, but this is a bit of a hassle. There are also recipes at ActiveState, such as http://code.activestate.com/recipes/364469/ that, while not identical to literal_eval, may be right for your purposes.

This still won't quite work, because you're also missing the closing right brace in the example string. I'm hoping that's a typo, in which case there's not a problem.

If not, you need to explain what you want it to actually do with such cases. Maybe auto-close any unclosed braces? If so, could unclosed brackets also be a problem?