PHP が str_replace を使用して多次元配列を置き換える方法の詳細な説明

$a = array(
'a' => 'bdc#',
'ceshi' => array('c'=>array('f'=>'#'))
);
$a = str_replace('#', 'ccc', $a);
var_dump($a);

array (size=2)
 'a' => string 'bdcccc' (length=6)
 'ceshi' =>
  array (size=1)
   'c' =>
    array (size=1)
     'f' => string '#' (length=1)

$a = array(
'a' => 'bdc#',
'ceshi' => array('c'=>array('f'=>'#'))
);
function strReplace(&$array) {
 $array = str_replace('#', 'ccc', $array);
if (is_array($array)) {
  foreach ($array as $key => $val) {
    if (is_array($val)) {
      strReplace($array[$key]);
    }
  }
}
}
strReplace($a);
var_dump($a);

array (size=2)
 'a' => string 'bdcccc' (length=6)
 'ceshi' =>
  array (size=1)
   'c' =>
    array (size=1)
     'f' => string 'ccc' (length=3)