JavaScript regex for specific pattern

Question

I'm want to apply a regex on a string like this word in $ctrl.words Want to find if the string has in and one string after and one before.

I try with this regex [a-zA-Z\\d]+\\s+in\\s+[a-zA-Z\\d]+', but the problem are the special characters from $ctrl.words, the regex always return false. The result what i want is true for string like this fruit in $ctrl.fruits letter in $ctrl.alphabet

And false for strings like fruit in $ctrl.fruits anything else letter in $ctrl.alphabet anithing else

What do you mean if the string has in and "one string after and one before?" Do you mean that there needs to be characters before and after the in - as separate words? Does the in need to have spaces around it? — LavaWings
– LavaWings, Commented Mar 1, 2018 at 18:18
Yes i'm need separate words before and after the in, and need have spaces too — user7436753
– user7436753, Commented Mar 1, 2018 at 18:21
Why are you escaping your backslashes? [a-zA-Z\\d] for example matches alphabetical characters, \, and d (redundantly) — Patrick Roberts
– Patrick Roberts, Commented Mar 1, 2018 at 18:23
@PatrickRoberts Backslashes should be doubled in RegExp constructor notation, when regex delimiters are not used. — Wiktor Stribiżew
– Wiktor Stribiżew, Commented Mar 1, 2018 at 18:24

Wiktor Stribiżew · Accepted Answer · 2018-03-01 18:26:30Z

2

Since you need to match a string that only consists of two non-whitespace char chunks separated with in enclosed with whitespaces, you may use

/^\S+\s+in\s+\S+$/

See the regex demo

Details

^ - start of string
\S+ - `+ non-whitespace chars
\s+in\s+ - an in substring enclosed with 1 or more whitespaces
\S+ - `+ non-whitespace chars
$ - end of string.

JS demo:

var strs = ['fruit in $ctrl.fruits', 'letter in $ctrl.alphabet', 'fruit in $ctrl.fruits anything else', 'letter in $ctrl.alphabet anithing else' ];
var rx = /^\S+\s+in\s+\S+$/;
for (var s of strs) {
  console.log(s, "=>", rx.test(s));
}

answered Mar 1, 2018 at 18:26

Wiktor Stribiżew

631k41 gold badges502 silver badges632 bronze badges

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

Collectives™ on Stack Overflow

JavaScript regex for specific pattern

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related