Get numbers from string with PHP

Question

I have strings:

$one = 'foo bar 4 baz (5 qux quux)';
$two = 'bar baz 2 bar';
$three =  'qux bar 12 quux (3 foo)';
$four = 'foo baz 3 bar (13 quux foo)';

How can I find the numeric digits in these strings?

Maybe with function:

function numbers($string){

    // ???

    $first = ?;
    $second = ?;
}

For example:

function numbers($one){

    // ???

    $first = 4;
    $second = 5;
}

function numbers($two){

    // ???

    $first = 2;
    $second = NULL;
}

Best way for this maybe is regex, but how can I use this for my example? Maybe without regex?

Answer 1

You can use regular expressions for this. The \d escape sequence will match all digits in the subject string.

For example:

<?php

function get_numerics ($str) {
    preg_match_all('/\d+/', $str, $matches);
    return $matches[0];
}

$one = 'foo bar 4 baz (5 qux quux)';
$two = 'bar baz 2 bar';
$three = 'qux bar 12 quux (3 foo)';
$four = 'foo baz 3 bar (13 quux foo)';

print_r(get_numerics($one));
print_r(get_numerics($two));
print_r(get_numerics($three));
print_r(get_numerics($four));

https://3v4l.org/DiDBL