正则表达式 - 在某个单词之后匹配4位数字作为完全匹配而不是组

Question

I'm having hard time trying to figure out regular expression that will extract 4 digits long number after certain word as full match.

Here is the text:

FV 7017 FOR SOMETHING 1076,33 USD.

and here is my regular expression to extract the 4 digits number:

/FV (\d{4,})/

That will result in:

Full match  = `FV 7017`
Group 1 match = `7017`

Is it possible to exclude that "FV" word using regex to have that result as full match?

Answer 1

4 steps faster than a positive lookbehind, is to use \K to restart the fullstring match.

/FV \K\d{4}/

Pattern Demo

PHP Implementation:

$string='FV 7017 FOR SOMETHING 1076,33 USD.';
echo preg_match('/FV \K\d{4}/',$string,$out)?$out[0]:'fail';
// output: 7017