Unicode example;
<?php
function array_change_key_case_unicode($arr, $c = CASE_LOWER) {
$c = ($c == CASE_LOWER) ? MB_CASE_LOWER : MB_CASE_UPPER;
foreach ($arr as $k => $v) {
$ret[mb_convert_case($k, $c, "UTF-8")] = $v;
}
return $ret;
}
$arr = array("FirSt" => 1, "yağ" => "Oil", "şekER" => "sugar");
print_r(array_change_key_case($arr, CASE_UPPER));
print_r(array_change_key_case_unicode($arr, CASE_UPPER));
?>
Array
(
[FIRST] => 1
[YAğ] => Oil
[şEKER] => sugar
)
Array
(
[FIRST] => 1
[YAĞ] => Oil
[ŞEKER] => sugar
)| CARVIEW |
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PHP: array_change_key_case - Manual
array_change_key_case
(PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8)
array_change_key_case — Changes the case of all keys in an array
Description
Returns an array with all keys from array lowercased
or uppercased. Numbered indices are left as is.
Return Values
Returns an array with its keys lower or uppercased.
Examples
Example #1 array_change_key_case() example
<?php
$input_array = array("FirSt" => 1, "SecOnd" => 4);
print_r(array_change_key_case($input_array, CASE_UPPER));
?>The above example will output:
Array
(
[FIRST] => 1
[SECOND] => 4
)
Notes
Note:
If an array has indices that will be the same once run through this function (e.g. "
keY" and "kEY"), the value that is later in the array will override other indices.
＋add a note
User Contributed Notes 12 notes
qeremy [atta] gmail [dotta] com ¶
13 years ago
xsaero00 ¶
11 years ago
Here is the most compact way to lower case keys in a multidimensional array
function array_change_key_case_recursive($arr)
{
return array_map(function($item){
if(is_array($item))
$item = array_change_key_case_recursive($item);
return $item;
},array_change_key_case($arr));
}
zhangxuejiang ¶
5 years ago
I improve the array_change_key_case_recursive function ,let it can lowercase or uppercase keys
function array_change_key_case_recursive($arr, $case = CASE_LOWER)
{
return array_map(function($item) use($case) {
if(is_array($item))
$item = array_change_key_case_recursive($item, $case);
return $item;
},array_change_key_case($arr, $case));
}
msegit post pl ¶
4 years ago
Improved multidimensional unicode func (after qeremy):
<?php
function array_change_key_case_unicode_recurs($arr, $c = CASE_LOWER) {
foreach ($arr as $k => $v) {
$ret[mb_convert_case($k, (($c === CASE_LOWER) ? MB_CASE_LOWER : MB_CASE_UPPER), "UTF-8")] = (is_array($v) ? array_change_key_case_unicode_recurs($v, $c) : $v );
}
return $ret;
}
$arr = array("FirSt" => 1, "ZażóŁć gęŚlą jaŹń" => array("yağ" => "Oil", "şekER" => "sugar") );
print_r(array_change_key_case($arr, CASE_UPPER));
print_r(array_change_key_case_unicode_recurs($arr, CASE_UPPER));
?>
Array
(
[FIRST] => 1
[ZAżóŁć GęŚLą JAŹń] => Array
(
[yağ] => Oil
[şekER] => sugar
)
)
Array
(
[FIRST] => 1
[ZAŻÓŁĆ GĘŚLĄ JAŹŃ] => Array
(
[YAĞ] => Oil
[ŞEKER] => sugar
)
)
andreas dot schuhmacher87 at googlemail dot com ¶
17 years ago
multibyte and multi-dimensional-array support, have fun!
<?php
define('ARRAY_KEY_FC_LOWERCASE', 25); //FOO => fOO
define('ARRAY_KEY_FC_UPPERCASE', 20); //foo => Foo
define('ARRAY_KEY_UPPERCASE', 15); //foo => FOO
define('ARRAY_KEY_LOWERCASE', 10); //FOO => foo
define('ARRAY_KEY_USE_MULTIBYTE', true); //use mutlibyte functions
/**
* change the case of array-keys
*
* use: array_change_key_case_ext(array('foo' => 1, 'bar' => 2), ARRAY_KEY_UPPERCASE);
* result: array('FOO' => 1, 'BAR' => 2)
*
* @param array
* @param int
* @return array
*/
function array_change_key_case_ext(array $array, $case = 10, $useMB = false, $mbEnc = 'UTF-8') {
$newArray = array();
//for more speed define the runtime created functions in the global namespace
//get function
if($useMB === false) {
$function = 'strToUpper'; //default
switch($case) {
//first-char-to-lowercase
case 25:
//maybee lcfirst is not callable
if(!function_exists('lcfirst'))
$function = create_function('$input', '
return strToLower($input[0]) . substr($input, 1, (strLen($input) - 1));
');
else $function = 'lcfirst';
break;
//first-char-to-uppercase
case 20:
$function = 'ucfirst';
break;
//lowercase
case 10:
$function = 'strToLower';
}
} else {
//create functions for multibyte support
switch($case) {
//first-char-to-lowercase
case 25:
$function = create_function('$input', '
return mb_strToLower(mb_substr($input, 0, 1, \'' . $mbEnc . '\')) .
mb_substr($input, 1, (mb_strlen($input, \'' . $mbEnc . '\') - 1), \'' . $mbEnc . '\');
');
break;
//first-char-to-uppercase
case 20:
$function = create_function('$input', '
return mb_strToUpper(mb_substr($input, 0, 1, \'' . $mbEnc . '\')) .
mb_substr($input, 1, (mb_strlen($input, \'' . $mbEnc . '\') - 1), \'' . $mbEnc . '\');
');
break;
//uppercase
case 15:
$function = create_function('$input', '
return mb_strToUpper($input, \'' . $mbEnc . '\');
');
break;
//lowercase
default: //case 10:
$function = create_function('$input', '
return mb_strToLower($input, \'' . $mbEnc . '\');
');
}
}
//loop array
foreach($array as $key => $value) {
if(is_array($value)) //$value is an array, handle keys too
$newArray[$function($key)] = array_change_key_case_ex($value, $case, $useMB);
elseif(is_string($key))
$newArray[$function($key)] = $value;
else $newArray[$key] = $value; //$key is not a string
} //end loop
return $newArray;
}
?>
shaman_master at list dot ru ¶
5 years ago
<?php
/**
* Convert keys in an array.
*
* @param array $array Source data
* @param callable $callback Function name (strtolower, strtoupper, ucfirst, lcfirst, ucwords)
* @return array
*/
function array_convert_key_case(array $array, callable $callback = 'strtolower')
{
return array_combine(
array_map($callback, array_keys($array)),
array_values($array)
);
}
?>
wendri dot net at gmail dot com ¶
2 years ago
Array of partitions with always the same number of sub-array indexes.
<?php
function partitionFixedSubArray($array, $length, $empty_space)
{
$result = [];
if ( sizeof($array) ) {
$result = array_chunk($array, $length);
$last_array_count = sizeof(end($result));
if ($last_array_count < $length) {
for ($i = $last_array_count; $i < $length; $i++) {
array_push($result[key($result)], $empty_space);
}
}
}
return $result;
}
$employees = [
"Paidi",
"Paijo",
"Darno",
"Kusnan",
"Mukidi",
"Sarno",
"Nurdin",
"Parmen",
"Sukinah",
"Sartini",
"Sukijan",
"Yono",
"Supoyo"
];
echo "<pre>";
print_r(partitionFixedSubArray($employees, 5, "empty space"));
echo "</pre>";
?>
Output:
Array
(
[0] => Array
(
[0] => Paidi
[1] => Paijo
[2] => Darno
[3] => Kusnan
[4] => Mukidi
)
[1] => Array
(
[0] => Sarno
[1] => Nurdin
[2] => Parmen
[3] => Sukinah
[4] => Sartini
)
[2] => Array
(
[0] => Sukijan
[1] => Yono
[2] => Supoyo
[3] => empty space
[4] => empty space
)
)
NetPanther ¶
12 years ago
Use this to capitalize first letter of all array keys:
<?php
function ucfirstKeys(&$data)
{
foreach ($data as $key => $value)
{
// Convert key
$newKey = ucfirst($key);
// Change key if needed
if ($newKey != $key)
{
unset($data[$key]);
$data[$newKey] = $value;
}
// Handle nested arrays
if (is_array($value))
{
ucfirstKeys($data[$key]);
}
}
}
$test = array('foo' => 'bar', 'moreFoo' => array('more' => 'foo'));
ucfirstKeys($test);
print_r($test);
?>
Result:
Array ( [MoreFoo] => Array ( [More] => foo ) [Foo] => bar )
cm at gameswelt dot de ¶
17 years ago
I just changed the code a little bit so you havent got a code that repeats itself.
<?php
function array_change_key_case_secure($array = array(), $case = CASE_UPPER){
$secure = array();
$functionWrap = array(CASE_UPPER => 'strtoupper',
CASE_LOWER => 'strtolower');
foreach($array as $key => $val){
if(isset($functionWrap[$key])){
$key = $functionWrap[$case]($key);
$secure[$key][] = $val;
} else {
die('Not a known Type');
}
}
foreach($secure as $key => $val){
if(count($secure[$key]) == 1){
$secure[$key] = $val[0];
}
}
return $secure;
}
$myArray = array('A' => 'Hello',
'B' => 'World',
'a' => 'how are you?');
print_r($myArray);
$myArray = array_change_key_case_secure($myArray);
print_r($myArray);
/*
Array
(
[A] => Hello
[B] => World
[a] => how are you?
)
Array
(
[A] => Array
(
[0] => Hello
[1] => how are you?
)
[B] => World
)
*/
john at doe dot com ¶
17 years ago
<?php
function array_change_value_case($input, $case = CASE_LOWER)
{
$aRet = array();
if (!is_array($input))
{
return $aRet;
}
foreach ($input as $key => $value)
{
if (is_array($value))
{
$aRet[$key] = array_change_value_case($value, $case);
continue;
}
$aRet[$key] = ($case == CASE_UPPER ? strtoupper($value) : strtolower($value));
}
return $aRet;
}
?>
anon at ymous dot com ¶
16 years ago
Below is a recursive version of this function.
<?php
/**
* A recursive array_change_key_case function.
* @param array $input
* @param integer $case
*/
function array_change_key_case_recursive($input, $case = null){
if(!is_array($input)){
trigger_error("Invalid input array '{$array}'",E_USER_NOTICE); exit;
}
// CASE_UPPER|CASE_LOWER
if(null === $case){
$case = CASE_LOWER;
}
if(!in_array($case, array(CASE_UPPER, CASE_LOWER))){
trigger_error("Case parameter '{$case}' is invalid.", E_USER_NOTICE); exit;
}
$input = array_change_key_case($input, $case);
foreach($input as $key=>$array){
if(is_array($array)){
$input[$key] = array_change_key_case_recursive($array, $case);
}
}
return $input;
}
?>
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