Regex Invalid quantifier?

Question

I'm using regexes with JavaScript and I'm having some trouble with one that returns me Invalid quantifier ?.

This is the code:

if(url.match(new RegExp('^https?://.+/foresee(?:-|_)surveydef\.js(?:\?)(.*)','g')) != null)

I read on other questions that I need to add a \ before the ? character but it does not fix it...

if(url.match(new RegExp('^https\?://.+/foresee(\?:-|_)surveydef\.js(\?:\?)(.*)','g')) != null)

The input url is http://marvel.com/, I just check for a match.

See http://stackoverflow.com/questions/3713290/javascript-invalid-quantifier-in-regex. Also, what is your input string? What is the expected behavior? There are potentially several issues (you are using a regex with a global modifier with `match`, that means all captured values are lost. — Wiktor Stribiżew, Oct 24 '16 at 17:55
You need to escape those slashes. And, given that you appear to be attempting to match a URL, I'd recommend escaping the dots too. — Sebastian Lenartowicz, Oct 24 '16 at 17:56
Ok, the `http://marvel.com/` does not contain a `?`. Using `\\?` won't help. What are the requirements? Match any URL? — Wiktor Stribiżew, Oct 24 '16 at 17:58
@WiktorStribiżew there can be different url's to match. I need to check if the url matches the regex expression. — Valip, Oct 24 '16 at 17:59
@SebastianLenartowicz I tried this, but the error is still there: `'events\.foreseeresults\.com\/rec\/process\?(.*)','g'` — Valip, Oct 24 '16 at 17:59
Works in Chrome console, with `'?'` or with `'\?'` either way — , Oct 24 '16 at 18:17
@WiktorStribiżew I was wrong about the code that caused the error...it was caused by another `else` statement that was on the same line (the code is not written by me). I updated my question, thank you! — Valip, Oct 24 '16 at 19:01

score 0 · Answer 1 · answered Oct 24 '16 at 19:14

0

Fixed it with the following code:

if(url.match(new RegExp('^https?://.+/foresee(?:-|_)surveydef\.js(\\?:\?)(.*)','g'))

answered Oct 24 '16 at 19:14

Valip

What are you doing with `(\\?:\?)`? Why use a RegExp constructor at all if your pattern is static? Your question is still unclear as you have not provided the input and expected output. Matching a `?` followed with an optional `:` does not make much sense. – Wiktor Stribiżew Oct 24 '16 at 19:36

1 Answers1