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?

You want to match only numerics? Not to convert `one` to `1` as well? — DaveRandom, Jun 28 '12 at 11:19
Your question is not clear, do you want to extract only numbers from a string? — Bud Damyanov, Jun 28 '12 at 11:19
Have a look at this... it will point you in direction... http://stackoverflow.com/questions/1077600/converting-words-to-numbers-in-php — Brian, Jun 28 '12 at 11:20
yes, i want to match only numerics. one, two etc are only examples words — Daniel Pairen, Jun 28 '12 at 11:24

DaveRandom · Accepted Answer · 2016-01-25T10:14:47.857

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

score 7 · Answer 2 · answered Jun 28 '12 at 11:21

7

You can do:

$str = 'string that contains numbers';
preg_match_all('!\d+!', $str, $matches);
print_r($matches);

answered Jun 28 '12 at 11:21

Leri

12,367
7
43
60

Greg · Answer 3 · 2014-10-14T14:22:15.213

Here's my attempt WITHOUT a regular expression

function getNumbers($str) {
    $result = array();

    // Check each character.
    for($i = 0, $len = strlen($str); $i < $len; $i++) {
        if(is_numeric($str[$i])) {
            $result[] = $str[$i];
        }
    }

    return $result;
}

$one = 'one two 4 three (5 four five)';
$two = 'one two 2 three';
$three =  'one two 12 three (3 four)';
$four = 'one two 3 three (13 four five)';

var_dump(getNumbers($one));
var_dump(getNumbers($two));
var_dump(getNumbers($three));
var_dump(getNumbers($four));

// Output:

array(2) {
  [0]=>
  string(1) "4"
  [1]=>
  string(1) "5"
}

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

array(3) {
  [0]=>
  string(1) "1"
  [1]=>
  string(1) "2"
  [2]=>
  string(1) "3"
}

array(3) {
  [0]=>
  string(1) "3"
  [1]=>
  string(1) "1"
  [2]=>
  string(1) "3"
}

`WITHOUT a regular expression` - Admirable, but silly for this job. Regex will be much better/faster here - especially since you are calling `strlen()` on every iteration rather that caching in a variable the result once before the loop. Try this with a large string (or maybe even a small one) and you will find regex is much faster. — DaveRandom, Jun 28 '12 at 11:26

Get numbers from string with PHP

3 Answers3

Linked

Related