How to iterate through the dictionaries of a string representation of a list of dictionaries?

Question

In such an example:

"[{'id' : 18, 'name' : 'Rick'}, {'id' : 19, 'name' : 'Luke'}]"

I am working with a str representation of a list of dicts. How can I iterate through the list to return a new list of all the "id's" in the dictionaries?

The desired result:

[18, 19]

EDIT: I have tried already to cast the string into a list with ast.literal_eval(foolist) and iterated through the items in the list. However, when I do this, it iterates through the characters in foolist starting with "{" then "'".

Well, start by converting it from a string to a real list of dicts. — BrenBarn, Jan 25 '18 at 03:19
Try `[d['id'] for d in eval(s)]`. `eval` helps you to convert the string into a list. — Zhiya, Jan 25 '18 at 03:20
Can you show the code you wrote using `ast.literal_eval`? It sounds like you didn't use it properly, so you were still iterating over the original string. — Blckknght, Jan 25 '18 at 03:51

score 2 · Accepted Answer · answered Jan 25 '18 at 04:19

2

As suggested in several comments:

import ast


foolist = "[{'id' : 18, 'name' : 'Rick'}, {'id' : 19, 'name' : 'Luke'}]"
[d["id"] for d in ast.literal_eval(foolist)]
# [18, 19]

answered Jan 25 '18 at 04:19

pylang

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score 0 · Answer 2 · answered Jan 25 '18 at 03:30

I guess this code would serve your purpose

a = "[{'id' : 18, 'name' : 'Rick'}, {'id' : 19, 'name' : 'Luke'}]"

a = a.split(',')
output = []
for data in a:
    data = data.replace('[', '').replace('{','').replace(']','').replace('}','').replace(' ','')
    if eval(data.split(':')[0]) == 'id':
        output.append(data.split(':')[1])
print(output)

score 0 · Answer 3 · answered Jan 25 '18 at 03:38

I have adapted a previous answer on Combining 2 dictionaries with common key.

def mergeDoLs(*dicts):
    def flatten(LoL):
        return [e for l in LoL for e in l]
    rtr= {k: [] for k in set(flatten(d for d in dicts))}
    for k, v in flatten(d.items() for d in dicts):
        rtr[k].append(v)
    return rtr

d_str = "[{'id' : 18, 'name' : 'Rick'}, {'id' : 19, 'name' : 'Luke'}]"
d = mergeDoLs(*eval(d_str))
d['id']

# output
# d = {'id': [18, 19], 'name': ['Rick', 'Luke']}
# d['id'] = [18, 19]

score 0 · Answer 4 · answered Jan 25 '18 at 03:53

Use JSON built-in library.

import json

raw_string = "[{'id' : 18, 'name' : 'Rick'}, {'id' : 19, 'name' : 'Luke'}]"
json_string = raw_string.replace('\'', '"') #converting NON-JSON string to JSON string


my_dictionary = dict()
my_dictionary = json.loads(json_string)

ids = []

for item in my_dictionary:
    ids.append(int(item['id']))

print(ids)

score 0 · Answer 5 · answered Jan 25 '18 at 07:38

I tried this:-

import json

a = "[{'id' : 18, 'name' : 'Rick'}, {'id' : 19, 'name' : 'Luke'}]"
final_list = []
a = a.replace("'",'"')
b = '{"chck":'+a+"}"
b = json.loads(b)
for i in b.values():
    for j in i:
        final_list.append(j['id'])
print (final_list)

score 0 · Answer 6 · answered Jan 27 '18 at 08:18

0

Just try this method :

import ast

data="[{'id' : 18, 'name' : 'Rick'}, {'id' : 19, 'name' : 'Luke'}]"


print(list(map(lambda x:x['id'],ast.literal_eval(data))))

output:

[18, 19]

answered Jan 27 '18 at 08:18

How to iterate through the dictionaries of a string representation of a list of dictionaries?

6 Answers6