How do I regex match a pattern with optional surrounding parentheses?

Question

I'm looking for a single line regular expression which matches a pattern with optional parentheses. When the parentheses are present they should not be included in the matched pattern.

The following bold text demonstrates what should / shouldn't match:

Should Match:

"Title Description (AAA123)"

"(ABC000) Title Description"

"Title Description DEF999"

"Title - RST321 - Description"

Shouldn't Match:

"Title Description AB123"

"Title Description CCC456a"

"Title Description (ABE999c)"

@Rohit Jain Instead of making it a good edit. You messed it. — Bhushan Firake, Feb 12 '13 at 13:53
@RohitJain: Tried this "()?([a-zA-Z]{3}[0-9]{3})()?" but it matches the end character regardless of whether its a parenthesis or not — Brian Scott, Feb 12 '13 at 14:09
@nhahtdh: Using .Net but can translate any regex statement as required. — Brian Scott, Feb 12 '13 at 14:14
Do you want `DFG456` in `Title_Description_DFG456` to be matched? — nhahtdh, Feb 12 '13 at 14:14

score 3 · Accepted Answer · answered Feb 12 '13 at 14:07

3

Try this regex:

\b[a-zA-Z]{3}\d{3}\b

This matches:

# \b          - A word boundary,
# [a-zA-Z]{3} - followed by 3 letters,
# \d{3}       - followed by 3 digits,
# \b          - followed by a word boundary.

The regex doesn't care about parentheses, like requested, but doesn't match strings that are too long.

answered Feb 12 '13 at 14:07

Cerbrus

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You will also match `___345` and `234456` – nhahtdh Feb 12 '13 at 14:11
@nhahtdh: Whoops, I didn't think of `\w` also matching those. Edited, thanks! – Cerbrus Feb 12 '13 at 14:12
@Cerbrus: Excellent, the \b was the missing key for me. I didn't know how to match either empty space or a parenthesis at the same time. Thanks. – Brian Scott Feb 12 '13 at 14:16
No problem, @Brian! I'd suggest having a look at [this site](http://www.regular-expressions.info), it has a lot of useful info on regexes. Thanks for accepting my answer ^_^ – Cerbrus Feb 12 '13 at 14:26

How do I regex match a pattern with optional surrounding parentheses?

1 Answers1