camelize + underscore in php

underscore.php

<?php

  /**
  * Transforms an under_scored_string to a camelCasedOne
  */
  function camelize($scored) {
    return lcfirst(
      implode(
        '',
        array_map(
          'ucfirst',
          array_map(
            'strtolower',
            explode(
              '_', $scored)))));
  }

  /**
  * Transforms a camelCasedString to an under_scored_one
  */
  function underscore($cameled) {
    return implode(
      '_',
      array_map(
        'strtolower',
        preg_split('/([A-Z]{1}[^A-Z]*)/', $cameled, -1, PREG_SPLIT_DELIM_CAPTURE|PREG_SPLIT_NO_EMPTY)));
  }

Super Awesome !!

Take a look at the same functions in Symfony's Container : https://github.com/symfony/symfony/blob/2.8/src/Symfony/Component/DependencyInjection/Container.php
Elegant + super-tested = 💯

function camelize($string) {
    return preg_replace('/[-_]([a-z])/e', 'strtoupper("$1")', $string);
}

function underscore($string) {
    return preg_replace('/([a-z])([A-Z])/e', '"$1" . strtolower("_$2")', $string); 
}

@MozzyMoz flag /e is deprecated, so you code will not work on php v >= 5.5.0

@NemoD503, thanks for the heads-up. I was about to replace it with a preg_replace_callback but the camelize function in the Symfony DI-Container looks nicer

@nemo

function camelize(string $string): string
{
    return lcfirst(str_replace(' ', '', ucwords(preg_replace('/[^a-zA-Z0-9\x7f-\xff]++/', ' ', $string))));
}