get integers from alphanumeric string in php code example

Example 1: PHP random string generator

function generateRandomString($length = 25) {
    $characters = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
    $charactersLength = strlen($characters);
    $randomString = '';
    for ($i = 0; $i < $length; $i++) {
        $randomString .= $characters[rand(0, $charactersLength - 1)];
    }
    return $randomString;
}
//usage 
$myRandomString = generateRandomString(5);

Example 2: php get only numbers

$str = 'In My Cart : 11 items';
$int = (int) filter_var($str, FILTER_SANITIZE_NUMBER_INT);