array_combine(array_map("strtolower", array_keys($a)), array_values($a))
mario
2010-06-05 18:21:00
+1
A:
Doesn't recurse, but probably a good start to speed up his code
Erik
2010-06-05 18:25:53
Works with arrays, but doesn't work with objects.
tstenner
2010-06-05 18:31:06
Correction: works with arrays, as long as you cast them using `(array) $a`
tstenner
2010-06-05 18:37:05
+3
A:
Foreach is using an internal copy that is then traversed. Try it without:
function keysToLower($obj)
{
$type = (int) is_object($obj) - (int) is_array($obj);
if ($type === 0) return $obj;
reset($obj);
while (($key = key($obj)) !== null)
{
$element = keysToLower(current($obj));
switch ($type)
{
case 1:
if (!is_int($key) && $key !== ($keyLowercase = strtolower($key)))
{
unset($obj->{$key});
$key = $keyLowercase;
}
$obj->{$key} = $element;
break;
case -1:
if (!is_int($key) && $key !== ($keyLowercase = strtolower($key)))
{
unset($obj[$key]);
$key = $keyLowercase;
}
$obj[$key] = $element;
break;
}
next($obj);
}
return $obj;
}
Or use references to avoid that a copy is used:
function &keysToLower(&$obj)
{
$type = (int) is_object($obj) - (int) is_array($obj);
if ($type === 0) return $obj;
foreach ($obj as $key => &$val)
{
$element = keysToLower($val);
switch ($type)
{
case 1:
if (!is_int($key) && $key !== ($keyLowercase = strtolower($key)))
{
unset($obj->{$key});
$key = $keyLowercase;
}
$obj->{$key} = $element;
break;
case -1:
if (!is_int($key) && $key !== ($keyLowercase = strtolower($key)))
{
unset($obj[$key]);
$key = $keyLowercase;
}
$obj[$key] = $element;
break;
}
}
return $obj;
}
Gumbo
2010-06-05 18:27:37
Works fine except with nested arrays without keys every array on the second level is empty, e.g. `keysToLower(array(array(array(1,2))))` returns `array(0=>array())`
tstenner
2010-06-05 18:55:30
And the `if($key !== $keyLowercase)` prevents values in an array with a lowercase key from being processed, e.g. `array('lowercase'=>array('UPPERCASE'=>1))` won't work.Inserting an `else $val=keysToLower($val);` fixes this.
tstenner
2010-06-05 18:58:34
tstenner
2010-06-05 19:09:02
I just checked, it runs about 30% faster than my version, moving the `is_int` in the switch statement and unsetting the old key first slows it down again.
tstenner
2010-06-05 19:34:41
Creating a new object instead of unsetting the old keys speeds it up in my case.
tstenner
2010-06-05 21:07:26
A:
I assume you don't care about casting to array...
function keys_to_lower($o) {
if (is_object($o)) {
$o = (array)$o;
}
if (is_array($o)) {
return array_map('keys_to_lower', array_change_key_case($o));
}
else {
return $o;
}
}
Oblio
2010-06-05 19:54:07
I do care, but I will measure, whether doing this and recasting it back before returning will make any difference.
tstenner
2010-06-05 20:20:55