PHP如何从字符串中提取3位数并输出它

Question

This is a bit a strange issue. I am trying just to get sequential 3 digit integer from a string.

Now I thought I was successfully doing it using this code below...

preg_match_all('!\d+!', $image['title'], $integer); echo $integer[0][2];

But now it seems to be failing on some strings.

It works fine on these strings...

1. TZR9000 Supertroop 2014 001
2. FZR Mode 900 Impact 2014 003 Accessories
3. NICE750 Destroyer 2014 020

But then it fails on this string...

1. We like the moon 2013 Stand 010

Is there another possible way to extract the 3 digit integer successfully with out getting confused with other integers. I guess it will have to be a clever bit of php to do this.

The only consistent pattern there is, is there is always a space infront of the 3 digits and either a full-stop or a space after the 3 digits.

Answer 1

the solidest way should be

preg_match_all('!(\d{3})(?=(?:(?!\d{3}).)*$)!m', $str, $integer);

see it in action here: http://regex101.com/r/pJ0xN4

here's also a structural explanation: