Find a way to find characters that doesn't match the Regex is javascript

Question

I am trying to find a way to determine which character in my string does not match the regex, is there a way to do so in Javascript?

I've been using the regex object and i was able to determine whether a string matches the regex but i would like to go step further to determine why a string does not match the regex.

any thoughts?

This was what I currently have ... i am just trying to make sure a string only contains the set of characters found in the following regex ... and i would like to see which character does not match.

Here's my code :

var regexTest = new RegExp("^[0-9a-zA-Z\\!\\040\\@\\s\\#\\$\\%\\&\\*\\(\\)\\_\\+\\:\\\"\\<\\>\\?\\-\\=\\;\\'\\,\\.\\\\]+$",g); var bValid = regexTest.test(value); //this will check whether the value is valid ...

I've tried using value = value.replace(regexTest,''), but was unable to actually filter out the characters.

I don't think this is really well defined in general. Which character in "aababb" doesn't match the regex /^a*b*$/? Which character in "aaaccc" doesn't match the regex /^a+b+c+$/? Which character in "" (ie: the empty string) doesn't match the regex /a+/? — Laurence Gonsalves
– Laurence Gonsalves, Commented Feb 9, 2012 at 17:14

Paul · Accepted Answer · 2012-02-09 18:22:11Z

6

You could replace all the characters that do match with '', leaving only the things that don't match:

'abc123'.replace(/([a-z]+)/g, '') // "123"

edited Feb 9, 2012 at 18:22

Paul

142k28 gold badges285 silver badges272 bronze badges

answered Feb 9, 2012 at 17:13

Blender

300k55 gold badges462 silver badges511 bronze badges

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

4 Comments

Ben Carey Over a year ago

Ah, you meant catch the unmatched terms. Apologies, I misread. The above will sort your problem

aggietech Over a year ago

This doesn't seem to quite work - i've edited the question for some more clarity.

Blender Over a year ago

What does your huge regex do? Can you provide a test string?

aggietech Over a year ago

I did - just updated the question. Eventually decided to check the string one character as a time - don't think that's too nice of a solution but works for now.

Collectives™ on Stack Overflow

Find a way to find characters that doesn't match the Regex is javascript

1 Answer 1

4 Comments

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

4 Comments

Related