Increment integer in string

increment.php

<?php  

  function increment($matches) {
    return ++$matches[1];
  }

  $string = 'value1';
  $string =  preg_replace_callback( "|(\d+)|", 'increment', $string);
  echo $string; // value2

  // if u want to use in same class
  $string =  preg_replace_callback( "|(\d+)|", [$this, 'increment'], $string);