PHP: Remove all Characters from String except Numbers

That is not difficult, just use the following function for this:

$s = 'aANx182 29 ().';
$s = preg_replace('/[^0-9]/', '', $s);
echo $s;  // 18229

Explanation: First, we have a string $s containing all kinds of characters. Then we use the preg_replace function, with which we can perform replacements with the help of regular expressions. The function  excepts 3 parameters: What we are looking for, with which we want to replace and the input string.

We are looking for all characters that are not numbers, so we negate the set of numbers 0 to 9 ([^0-9]) as regular expression and replace all occurrences with an empty string (''). As input and third parameter, we are using our string $s from the beginning.

In the third line, we see our result: Only the numbers from the input string remained.
Last update on 2021-07-02 | Created on 2012-07-20