array_diff_assoc
you can use this function for return the difference of two array !
<?php
function array_unique_diff_key ($array1, $array2)
{
if (is_array($array1) && is_array($array2))
return array_diff_key($array1, $array2) + array_diff_key($array2, $array1);
else if (is_array($array1)) return $array1;
else if (is_array($array2)) return $array2;
else return array();
}
?>
array_diff_key
(PHP 5 >= 5.1.0)
array_diff_key — Calcula la diferencia de matrices usando las llaves para la comparación
Descripción
array array_diff_key
( array $array1
, array $array2
[, array $ ...
] )
array_diff_key() regresa una matriz conteniendo todos los valores de array1 que tienen llaves que no están presentes en cualquier otra matriz dada como parámetro. Note que la asociatividad es preservada. Esta función es como array_diff() excepto en que la comparación es hecha en las llaves en lugar de en los valores.
Example #1 Ejemplo array_diff_key()
<?php
$array1 = array('blue' => 1, 'red' => 2, 'green' => 3, 'purple' => 4);
$array2 = array('green' => 5, 'blue' => 6, 'yellow' => 7, 'cyan' => 8);
var_dump(array_diff_key($array1, $array2));
?>
El resultado del ejemplo seria:
array(2) { ["red"]=> int(2) ["purple"]=> int(4) }
Las dos llaves del par llave => valor, son consideradas iguales sólo si (string) $key1 === (string) $key2 . En otras palabras se revisa estrictamente el tipo de dato de tal manera que la representación del string debe ser el mismo.
Note: Note por favor que esta función solo revisa una dimensión de una matriz con n dimensiones. Por supuesto puede checar en forma más profunda usando la forma array_diff_key($array1[0], $array2[0]);.
Vea también array_diff(), array_udiff() array_diff_assoc(), array_diff_uassoc(), array_udiff_assoc(), array_udiff_uassoc(), array_diff_ukey(), array_intersect(), array_intersect_assoc(), array_intersect_uassoc(), array_intersect_key() y array_intersect_ukey().
add a note
User Contributed Notesarray_diff_key
division-par-zero at zilon dot net
03-Oct-2008 04:02
03-Oct-2008 04:02
Ashton
02-Apr-2008 11:33
02-Apr-2008 11:33
To return the unique elements (those with a key that exists only once in either array but not in both) try:
function array_unique_diff ($array1, $array2)
{
array_merge(array_diff_key($array1, $array2), array_diff_key($array2, $array1));
}
Example:
$array1 = array('blue' => 1, 'red' => 2, 'green' => 3, 'purple' => 4);
$array2 = array('green' => 5, 'blue' => 6, 'yellow' => 7, 'cyan' => 8);
array_diff_key($array1, $array2)
returns
array ( 'red' => 2, 'purple' => 4 )
array_diff_key($array2, $array1)
returns
array ( 'yellow' => 7, 'cyan' => 8, )
array_unique_diff($array1, $array2);
returns
array ( 'red' => 2, 'purple' => 4, 'yellow' => 7, 'cyan' => 8, )
sjungwirth at matrix-consultants dot com
28-Feb-2008 09:08
28-Feb-2008 09:08
I needed something a little different where maybe even the keys in multidimensional arrays don't match up. Setting $assoc to false will cause only to check for missing keys, otherwise it compares values as well. This was also based on '2ge at 2ge dot us' function
<?php
function n_array_diff_assoc ($a1, $a2, $assoc=true) {
$r = array();
if(is_array(current($a1))):
foreach($a1 as $k => $v):
if(isset($a2[$k])):
$diff = n_array_diff($a1[$k], $a2[$k], $assoc);
if (!empty($diff)):
$r[$k] = $diff;
endif;
else:
$r[$k] = $v;
endif;
endforeach;
else:
$r = $assoc ? array_diff_assoc($a1, $a2) : array_diff_key($a1, $a2);
endif;
return $r;
}
?>
coder at gs dot com
16-Feb-2008 11:00
16-Feb-2008 11:00
The PHP4 version below works only unidirectionally. If you switch the arrays around i.e. (ar2, ar1) you get different results than (ar1, ar2).
AiFiLTr0 [at host] invyl [dot] ath.cx
29-Nov-2007 02:56
29-Nov-2007 02:56
The recursive function suggested by '2ge at 2ge dot us' will provide you with empty arrays if there's no diff.
This variant of the function cleans up empty arrays and fixes a bug in the first suggested version. It works 100%
.
<?php
function array_diff_key_recursive ($a1, $a2) {
foreach($a1 as $k => $v) {
//$r[$k] = is_array($v) ? $this->array_diff_key_recursive($a1[$k], $a2[$k]) : array_diff_key($a1, $a2);
if (is_array($v))
{
$r[$k]=$this->array_diff_key_recursive($a1[$k], $a2[$k]);
}else
{
$r=array_diff_key($a1, $a2);
}
if (is_array($r[$k]) && count($r[$k])==0)
{
unset($r[$k]);
}
}
return $r;
}
?>
contact at autonoma dot fr
30-Jun-2007 02:01
30-Jun-2007 02:01
after kwutzke's comment , here is a PHP4 array_diff_key fonction for those in need
function PHP4_array_diff_key()
{
$arrs = func_get_args();
$result = array_shift($arrs);
foreach ($arrs as $array) {
foreach ($result as $key => $v) {
if (array_key_exists($key, $array)) {
unset($result[$key]);
}
}
}
return $result;
}
works for me, enjoy.
kwutzke @ somewhere in the net
20-Dec-2006 01:27
20-Dec-2006 01:27
PHP4 array_diff_key can be copied from the array_intersect_key implementation posted by some anonymous user on 2006-07-17. The only thing you have to do is to delete the '!' in the if and rename the function.
2ge at 2ge dot us
07-Mar-2006 08:28
07-Mar-2006 08:28
Hello, if you need diff key of n-dimensional arrays here is nice solution:
<?php
function n_array_diff ($a1, $a2) {
foreach($a1 as $k => $v) {
$r[$k] = is_array($v) ? n_array_diff($a1[$k], $a2[$k]) : array_diff_key($a1, $a2);
}
return $r;
}
?>
it will print everything, what is missing in $a2.
vlad_mustafin at ukr dot net
13-Jan-2006 04:39
13-Jan-2006 04:39
One more alternative variant :)
<?
if (!function_exists('array_diff_key')) {
function array_diff_key() {
$argCount = func_num_args();
$diff_arg_prefix = 'diffArg';
$diff_arg_names = array();
for ($i=0; $i < $argCount; $i++) {
$diff_arg_names[$i] = 'diffArg'.$i;
$$diff_arg_names[$i] = array_keys((array)func_get_arg($i));
}
$diffArrString = '';
if (!empty($diff_arg_names)) $diffArrString = '$'.implode(', $', $diff_arg_names);
eval("\$result = array_diff(".$diffArrString.");");
return $result;
}
}
?>
ampf at egp dot up dot pt
25-Nov-2005 09:55
25-Nov-2005 09:55
Well, you could implement in the code something more powerfull:
http://www.php.net/manual/en/function.array-diff.php#31364
ml at iceni dot pl
07-Jun-2005 09:52
07-Jun-2005 09:52
You may obtain this function with PEAR Package PHP_Compat (http://pear.php.net/package/PHP_Compat)
Then using such code is quite useful
<?php
if(!function_exists('array_diff_key')){
require_once 'PHP/Compat/Function/array_diff_key.php';
}
?>
maxence at pontapreta dot net
27-May-2005 07:38
27-May-2005 07:38
Seems to be a great function, especially for n-dimensions arrays. The only problem is that I cannot find it in php 5.0.3 and 5.0.4. Does it really exist ?! :(
[20:27:05][maxence@conurb] ~/test2/php-5.0.4$ grep PHP_FUNCTION * -r | grep -i array_diff_key
[20:27:09][maxence@conurb] ~/test2/php-5.0.4$
nicolas at goinf dot com
14-Apr-2005 05:28
14-Apr-2005 05:28
Be aware that the last solution doesn't work if for any reason, two values are the same.
eric dot broersma at phil dot uu dot nl
05-Mar-2005 03:58
05-Mar-2005 03:58
<?php
function array_diff_key()
{
$args = func_get_args();
return array_flip(call_user_func_array('array_diff',
array_map('array_flip',$args)));
}
?>
denis noessler
23-Nov-2004 01:07
23-Nov-2004 01:07
if (!function_exists('array_diff_key'))
{
/**
* Computes the difference of arrays using keys for comparison
*
* @param array $valuesBase Base elements for comparison, associative
* @param array $valuesComp[,..] Comparison elements, associative
*
* @param array Elements, not existing in comparison element, associative
*/
function array_diff_key()
{
$argCount = func_num_args();
$argValues = func_get_args();
$valuesDiff = array();
if ($argCount < 2)
{
return false;
}
foreach ($argValues as $argParam)
{
if (!is_array($argParam))
{
return false;
}
}
foreach ($argValues[0] as $valueKey => $valueData)
{
for ($i = 1; $i < $argCount; $i++)
{
if (isset($argValues[$i][$valueKey]))
{
continue 2;
}
}
$valuesDiff[$valueKey] = $valueData;
}
return $valuesDiff;
}
}