parsing string to a dict

Question

I have a string output which is in form of a dict ex.

{'key1':'value1','key2':'value2'}

how can make easily save it as a dict and not as a string?

What? Why not save the dict as a dict instead of creating a string in the first place? Please provide some more context on this. The question makes very little sense and indicated far larger and deeper problems may have lead to this. — S.Lott, Oct 18 '09 at 19:59
As pointed out by Dave, http://stackoverflow.com/questions/988228/converting-a-string-to-dictionary is an exact duplicate of this — dbr, Oct 18 '09 at 23:56
This was answered quite well in previous question [988228](http://stackoverflow.com/questions/988228/) — Dave, Oct 18 '09 at 16:56

unutbu · Accepted Answer · 2011-07-31T02:09:46.690

6

astr is a string which is "in the form of a dict". ast.literal_eval converts it to a python dict object.

In [110]: import ast

In [111]: astr="{'key1':'value1','key2':'value2'}"

In [113]: ast.literal_eval(astr)
Out[113]: {'key1': 'value1', 'key2': 'value2'}

edited Jul 31 '11 at 02:09

answered Oct 18 '09 at 16:16

unutbu

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Note that this using `eval` is not such a good idea if there's any way `astr` can contain, say, `os.remove("foo")`. – Robert Rossney Oct 18 '09 at 17:14

score 4 · Answer 2 · edited Oct 18 '09 at 23:48

4

This is best if you're on Python 2.6+, as it's not subject to the security holes in eval.

import ast

s = """{'key1':'value1','key2':'value2'}"""
d = ast.literal_eval(s)

edited Oct 18 '09 at 23:48

dbr

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answered Oct 18 '09 at 22:57

FogleBird

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You messed up the quotes. Use double quotes for the outside ones. – Chris Lutz Oct 18 '09 at 23:11

Oduvan · Answer 3 · 2009-10-19T07:34:36.813

1

using json.loads - may be faster

edited Oct 19 '09 at 07:34

answered Oct 18 '09 at 22:27

Oduvan

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score 1 · Answer 4 · answered Oct 19 '09 at 01:38

Where are you getting this string from? Is it in JSON format? or python dictionary format? or just some ad-hoc format that happens to be similar to python dictionaries?

If it's JSON, or if it's only a dict, and only contains strings and/or numbers, you can use json.loads, it's the most safe option as it simply can't parse python code.

This approach has some shortcomings though, if for instance, the strings are enclosed in single quotes ' instead of double quotes ", not to mention that it only parses json objects/arrays, which only coincidentally happen to share similar syntax with pythons dicts/arrays.

Though I think it's likely the string you're getting is intended to be in JSON format. I make this assumption because it's a common format for data exchange.

parsing string to a dict

4 Answers4