Python：在两个字符串之间找到一个字符串，重复

Question

I'm new to Python and still learning about regular expressions, so this question may sound trivial to some regex expert, but here you go. I suppose my question is a generalization of this question about finding a string between two strings . I wonder: what if this pattern (initial_substring + substring_to_find + end_substring) is repeated many times in a long string? For example

test='someth1 var="this" someth2 var="that" '
result= re.search('var=(.*) ', test)
print result.group(1)
>>> "this" someth2 var="that"

Instead, I'd like to get a list like ["this","that"] . How can I do it?

Answer 1

Use re.findall() :

result = re.findall(r'var="(.*?)"', test)
print(result)  # ['this', 'that']

If the test string contains multiple lines, use the re.DOTALL flag.

re.findall(r'var="(.*?)"', test, re.DOTALL)

Answer 2

The problem with your current regex is that the capture group (.*) is an extremely greedy statement. After the first instance of a var= in your string, that capture group will get everything after it.

If you instead decrease the generalization of the expression to var="(\\w+)" , you will not have the same issue, therefore changing that line of python to:

result = re.findall(r'var="([\w\s]+)"', test)