RegEx for checking multiple matches

Question

I want to match all occurrence in string.

Example:

pc+pc2/pc2+pc2*rr+pd

I want to check how many matched of pc2 value and regular expression is before and after special character exists.

var str = "pc+pc2/pc2+pc2*rr+pd"; 
var res = str.match(new RegExp("([\\W])pc2([\\W])",'g'));

But I got only +pc2/ and +pc2* and /pc2+ not get in this.

Problem is in first match / is removed. So after that, it is starting to check from pc2+pc2*rr+pd. That's why /pc2+ value does not get in the match.

How do I solve this problem?

Or, if you mean overlapping matches, `let res = [..."pc+pc2/pc2+pc2*rr+pd".matchAll(/(?=(\Wpc2\W))\W/g)]` and then `Array.from(res, x => x[1])` — Wiktor Stribiżew, May 21 '19 at 22:15
@WiktorStribiżew It is not a duplicate question. I want `+pc2/`, `+pc2*` and `/pc2+`. Have you got it? — Dhaduk Mitesh, May 22 '19 at 04:55
Your answer is [here](https://stackoverflow.com/a/33903830/3832970). All you need is to extract overlapping matches. It is a very frequent issue, that is why I preferred to close rather than answer. Answers to duplicate questions are often downvoted, and that is not something anyone wants at SO. — Wiktor Stribiżew, May 22 '19 at 06:57

score 0 · Answer 1 · answered May 21 '19 at 12:58

0

You need some sort of recursive regex to achieve what you're trying to get, you can use exec to manipulate lastIndex in case of value in string is p

let regex1 = /\Wpc2\W/g;
let str1 = 'pc+pc2/pc2+pc2*rr+pd';
let array1;
let op = []
while ((array1 = regex1.exec(str1)) !== null) {
  op.push(array1[0])
  if(str1[regex1.lastIndex] === 'p'){
    regex1.lastIndex--;
  }
}


console.log(op)

answered May 21 '19 at 12:58

Code Maniac

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It is working but `if(str1[regex1.lastIndex] === 'p'){` this is static code for `pc2`. Because I only match pc2 not other value. – Dhaduk Mitesh May 21 '19 at 13:37
@DhadukMitesh you can use regex library which supports recursive regex, you can even make the above function generic, i have added answer as per your specified question – Code Maniac May 21 '19 at 16:34
Yes, @code. But I want the dynamic code to find value. – Dhaduk Mitesh May 22 '19 at 04:45

RegEx for checking multiple matches

Example:

1 Answers1