Python String replace based on chars NOT in RegEx

Question

Is it possible to create a reqex that finds characters that are NOT is a specific set?

Rather than Blacklisting a bunch of characters and replacing them, it would be easier for me to allow a certain set and replace characters that are not in that set.

My set looks like this: [.a-zA-Z0-9]

I would like to do something like this:

clean_filename = re.sub(r'([.a-zA-Z0-9])', "_", filename)

obviously this code would replace the characters I want to keep, is there a way to replace the characters NOT in that set?

ThiefMaster · Accepted Answer · 2011-03-03 16:23:43Z

37

Yes, use the ^ negation "modifier": r'[^.a-zA-Z0-9]'

answered Mar 3, 2011 at 16:23

ThiefMaster

320k85 gold badges608 silver badges648 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

usr Over a year ago

The user could enter ".." as a file name. Would that be ok?

Petri Lehtinen · Accepted Answer · 2011-03-03 16:24:19Z

6

clean_filename = re.sub(r'[^.a-zA-Z0-9]', "_", filename)

answered Mar 3, 2011 at 16:24

Petri Lehtinen

2,1752 gold badges18 silver badges23 bronze badges

Comments

hsz · Accepted Answer · 2011-03-03 16:24:11Z

5

Try with:

re.sub(r'[^a-zA-Z0-9]', "_", filename)

answered Mar 3, 2011 at 16:24

hsz

153k63 gold badges268 silver badges320 bronze badges

Collectives™ on Stack Overflow

Python String replace based on chars NOT in RegEx

3 Answers 3

1 Comment

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

1 Comment

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related