How get a certain numeric value inside array of string in PHP?

Question

I have a String $line. For example,

$line = "stringA stringB 4-stringC stringD stringF 12345 stringG 678249 stringH ";

According to the var $line, there are 6 words of string, 2 numeric values, and 1 combination word of numeric and string.

I would like to catch a certain string which is a numeric value 12345. And this is my code that I just tried:

if (preg_match('/ ([0-9,]+)/', $line, $matches) === 1 && strlen($matches[0]) > 3 && strlen($matches[1]) > 3) {
    echo var_dump($matches[0]);
}

However, It seems like the code only take the first numeric value on the string, once it traced. And the result is:

array(2) {
  [0]=>
  string(2) " 4"
  [1]=>
  string(1) "4"
}

instead of 12345.

So, What is the 'Regular Expression' should I use, if I only like to catch string contain: 12345 ?

You can also do this: http://sandbox.onlinephpfunctions.com/code/85bb608816c3cbd81520ae7ffe5123bc45c5d5aa — Martin Dimitrov, Nov 20 '19 at 09:57
Well, just to answer your question. You can use `preg_match_all` to get more than one match. Because in your case, only the first match is checked by `preg_match`. Another option would be to rewrite the regex to find the `last occurence`. Or you could reverse the string before using `preg_match` with `strrev` (and then reverse the found match again). — Matthias S, Nov 20 '19 at 10:13
@jibsteroos how to set get $matches more than 4 digit, and manage in preg_match()? `'/ ([0-9,]+\d{5})/'` — Agnes Palit, Nov 20 '19 at 10:26
@MatthiasS I have tried `preg_match_all` but it didnt show result. Get the `last occurence` could be an solution, however, maybe it could be risky if there are another numeric string after `12345`. Do you have any advice for this? — Agnes Palit, Nov 20 '19 at 10:51
@AgnesPalit This post is reopened. Did any of the solutions mentioned in the comments work for you? — The fourth bird, Nov 20 '19 at 17:04
@Thefourthbird yes, your answer is the one that I use and it works well — Agnes Palit, Nov 27 '19 at 17:02

score 3 · Accepted Answer · answered Nov 27 '19 at 17:06

You could use word boundaries \b and match 4 or more digits using a quantifier {4,}

\b\d{4,}\b

For example

$line = "string string 4-string string string 12345 string 678249 string ";
if (preg_match('/\b\d{4,}\b/', $line, $matches)) {
    var_dump($matches);
}

Output

array(1) {
  [0]=>
  string(5) "12345"
}

Php demo

How get a certain numeric value inside array of string in PHP?

1 Answers1