Javascript Regex for a partial string match only

Question

I need to write a JavaScript RegEx that matches only the partial strings in a word.

For example if I search using the string 'atta'

it should return

true for khatta
true for attari
true for navrattan
false for atta

I am not able to figure how to get this done using one RegEx. Thanks!

Lee Kowalkowski · Accepted Answer · 2014-05-28 10:24:00Z

9

You want to use a non-word boundary \B here.

/\Batta|atta\B/

edited May 28, 2014 at 10:24

answered May 28, 2014 at 9:52

Lee Kowalkowski

11.8k3 gold badges43 silver badges49 bronze badges

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

6 Comments

Per Hornshøj-Schierbeck Over a year ago

I think this is a much cleaner answer than mine

MaxArt Over a year ago

Good one. I may add that for test the capturing group is useless and memory consuming. I wonder if !/\batta\b/.test(string) isn't any faster...

Lee Kowalkowski Over a year ago

@MaxArt would that not also match "foobar"? If you're really worried about capturing groups, use a non-capturing group: /(?:\Batta|atta\B)/

maurya8888 Over a year ago

I believe !/\batta\b/.test(string) will return true for "this too". I need a partial match at least.

MaxArt Over a year ago

Yep, /\batta\b/ would match strings that also don't contain "atta" at all - I guess OP doesn't want that. @LeeKowalkowski There's no need to have groups either, in this case.

|

Per Hornshøj-Schierbeck · Accepted Answer · 2014-05-28 09:51:54Z

2

sp00m almost got it right

^(atta.+|.+atta|.+atta.+)$

Fiddle.

If whitespace is not allowed you could write

^(atta[\S]+|[\S]+atta|[\S]+atta[\S]+)$

edited May 28, 2014 at 9:51

answered May 28, 2014 at 9:46

Per Hornshøj-Schierbeck

15.2k21 gold badges84 silver badges103 bronze badges

2 Comments

sp00m Over a year ago

Or even ^(atta.+|.+atta.*)$ ;)

chris97ong Over a year ago

Hmm...so atta gives false but atta gives true.

Collectives™ on Stack Overflow

Javascript Regex for a partial string match only

2 Answers 2

6 Comments

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

6 Comments

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related