I have a string like this:

var variable = 'one|two|three|four|five';

This regex /^(\w+)\|/ matches first word (from left side). In other word, $1 returns one. Now I need to get second word from the right side (four).

EX1:

var variable = 'one|two|three';

I want two.

EX2:

var variable = 'one|two|three|four';

I want three.

EX3:

var variable = 'one|two|three|four|five|six|seven';

I want six.

Always I want second word from the right side. How can I do that?

I have a string like this:

var variable = 'one|two|three|four|five';

This regex /^(\w+)\|/ matches first word (from left side). In other word, $1 returns one. Now I need to get second word from the right side (four).

EX1:

var variable = 'one|two|three';

I want two.

EX2:

var variable = 'one|two|three|four';

I want three.

EX3:

var variable = 'one|two|three|four|five|six|seven';

I want six.

Always I want second word from the right side. How can I do that?

• javascript
• regex

• Let's see your Javascript code as well. – MortenMoulder Commented Feb 19, 2016 at 21:27
• 2 str.match(/\|(\w+)\|\w+$/)[1]. In JS, there is no other way. – Wiktor Stribiżew Commented Feb 19, 2016 at 21:28
• @Snorlax What? Actually I need to check if(variable.test(/second-word-form-right/) == 'four') { return true; } – stack Commented Feb 19, 2016 at 21:29
• What about one|two? Would you want one? – Brendan Abel Commented Feb 19, 2016 at 21:30
• @WiktorStribiżew Yep ..... – stack Commented Feb 19, 2016 at 21:31

5 Answers 5

Try this:

/\w+(?=\|\w+$)/

var regexp = /\w+(?=\|\w+$)/;

document.write(`<pre>
${[
  'one|two|three',
  'one|two|three|four',
  'one|two|three|four|five',
  'one|two|three|four|five|six'
].map(input=>`${input}=>${regexp.exec(input)[0]}`).join('\n')}
</pre>`)

If that doesn't convince you, here's a link to regex 101 demonstrating it as well.

If a lookahead is too slow for you, you can also try:

/(\w+)\|\w+$/

which still does the same thing, except now the result is stored in a group instead of returned directly, so change regexp.exec(input)[0] to regexp.exec(input)[1]:

var regexp = /(\w+)\|\w+$/;

document.write(`<pre>
${[
  'one|two|three',
  'one|two|three|four',
  'one|two|three|four|five',
  'one|two|three|four|five|six'
].map(input=>`${input}=>${regexp.exec(input)[1]}`).join('\n')}
</pre>`)

Alternatively, if you want to do this with pure regular expressions, you can actually do this:

(?:(.*)\|){2}

Check out the matched group on this: http://regexr./3crfr

Then for Javascript (or any other language), simply extract the group. You could do that like this:

var variable = 'one|two|three|four';
console.log(/(?:(.*)\|){2}/g.exec(variable)[1]);

Works fine, yeah?

Ignoring the regular expression, you can do this:

var variable = 'one|two|three|four';
var result = variable.split("|");
console.log(result[result.length - 2]);

If you want to do it with a regular expression, you can do this:

var variable = 'one|two|three|four';
console.log(variable.match(/\|(\w+)\|\w+$/)[1]);

Either way works fine.

An iterative approach , beginning at the end of input string. At first | character begin inner loop, at second | character break outer loop

var variable = "one|two|three|four|five"
, i = variable.length
, match = [];
while (true) {
  if (variable[i] === "|") {
    while (variable[--i] !== "|") {
      match.push(variable[i]);
    }
    match = match.reverse().join("");
    break;
  }
  --i
};

console.log(match)

Or, you could use the EOL anchor like this [^|]+(?=\|[^|]+$)