Extract text between parenthesis and space using Javascript and regex

Question

I'm using Javascript to parse the following User-Agent string:

"Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:60.0) Gecko/20100101 Firefox/60.0"

I'd like to extract the word "Windows" between the first parenthesis and a space. How can I use regular expressions in Javascript to do this?

I feel like regex isn't the best way to do this. Since you just want the word after the first parenthesis, you could find the first instance of `(`, then find the first instance of `[space]` after it, and then take the substring between them. — Thomas Cohn, Jun 14 '18 at 17:34
If you are looking to perform operations on the User-agent string then I would suggest a battle-tested library might be more suitable than regex. — John, Jun 14 '18 at 17:45
Maybe it helps: [Detecting OS Windows](https://stackoverflow.com/a/27862868/6188402) — Washington Guedes, Jun 14 '18 at 19:01

Luis felipe De jesus Munoz · Accepted Answer · 2018-06-14T18:35:01.537

0

If you only one the first word after the first parentheses you can use this regex: /\((\w+)/g

var string = "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:60.0) Gecko/20100101 Firefox/60.0";

console.log(/\((\w+)/g.exec(string)[1] || 0)

edited Jun 14 '18 at 18:35

answered Jun 14 '18 at 17:34

Luis felipe De jesus Munoz

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Did you think of strings that won't match your criteria ? Error would be throws as you would be accessing [1] of null. – user3210641 Jun 14 '18 at 17:43
Why not using `\w` instead of `[^ ]`? It seems more clear to me. – Marco Luzzara Jun 14 '18 at 18:33

score 0 · Answer 2 · answered Jun 14 '18 at 17:40

You can use String.match():

// Your input string
const string = 'Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:60.0) Gecko/20100101 Firefox/60.0';

// Find string
const match = string.match(/\((.+?)\s/);

// If string was found
if (match !== null) {
  // Get the result
  // match[0] is this whole matched string
  // match[1] is just the matched group
  const result = match[1];
  
  // So something with the result
  console.log(result);
}

Extract text between parenthesis and space using Javascript and regex

2 Answers2