Clash Royale CLAN TAG#URR8PPP

Find a string within a string using pattern matching in python

I'd like to use part of a string ('project') that is returned from an API. The string looks like this:

'Project Title': 'LS003942_EP - 5 Random Road, Sunny Place, SA 5000'


I'd like to store the 'LS003942_EP... ' part in a new variable called foldername. I'm thought a good way would be to use a regex to find the text after Title. Here's my code:

foldername

Title

orders = api.get_all(view='Folder', fields='Project Title', maxRecords=1)
for new in orders:
print ("Found 1 new project")
print (new['fields'])
project = (new['fields'])
s = re.search('Title(.+?)', result)
if s:
foldername = s.group(1)
print(foldername)


This gives me an error -

TypeError: expected string or bytes-like object.

I'm hoping for foldername = 'LS003942_EP - 5 Random Road, Sunny Place, SA 5000'

foldername = 'LS003942_EP - 5 Random Road, Sunny Place, SA 5000'

json.parse

ast.literal_eval()

eval

3 Answers
3

You can use ast.literal_eval to safely evaluate a string containing a Python literal:

ast.literal_eval

import ast

s = "'Project Title': 'LS003942_EP - 5 Random Road, Sunny Place, SA 5000'"

print(ast.literal_eval(s)['Project Title'])
# LS003942_EP - 5 Random Road, Sunny Place, SA 5000


It seems (to me) that you have a dictionary and not string. Considering this case, you may try:

s = 'Project Title': 'LS003942_EP - 5 Random Road, Sunny Place, SA 5000'

print(s['Project Title'])


If you have time, take a look at dictionaries.

print(repr(s['Project Title']))

I don't think you need a regex here:

regex

string = "'Project Title': 'LS003942_EP - 5 Random Road, Sunny Place, SA 5000'"
foldername = string[string.index(":") + 2: len(string)-1]


Essentially, I'm finding the position of the first colon, then adding 2 to get the starting index of your foldername (which would be the apostrophe), and then I use index slicing and slice everything from the index to the second-last character (the last apostrophe).

However, if your string is always going to be in the form of a valid python dict, you could simply do foldername = (eval(string).values)[0]. Here, I'm treating your string as a dict and am getting the first value from it, which is your desired foldername. But, as @AKX notes in the comments, eval() isn't safe as somebody could pass malicious code as a string. Unless you're sure that your input strings won't contain code (which is unlikely), it's best to use ast.literal_eval() as it only evaluates literals.

dict

foldername = (eval(string).values)[0]

dict

foldername

eval()

But, as @MaximilianPeters notes in the comments, your response looks like a valid JSON, so you could easily parse it using json.parse().

json.parse()

'Project Title': 'LS003942_EP - 5 Random Road, Sunny Place, SA 5000'

You could try this pattern: (?<='Project Title': )[^}]+.

(?<='Project Title': )[^}]+

Explanation: it uses positive lookbehind to assure, that match will occure after 'Project Title':. Then it matches until } is encountered: [^}]+.

'Project Title':

}

[^}]+

Demo

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