The array_diff_assoc_array from "chinello at gmail dot com" (and others) will not work for arrays with null values. That's because !isset is true when an array key doesn't exists or is set to null.
(sorry for the changed indent-style)
<?php
function array_diff_assoc_recursive($array1, $array2) {
$difference=array();
foreach($array1 as $key => $value) {
if( is_array($value) ) {
if( !isset($array2[$key]) || !is_array($array2[$key]) ) {
$difference[$key] = $value;
} else {
$new_diff = array_diff_assoc_recursive($value, $array2[$key]);
if( !empty($new_diff) )
$difference[$key] = $new_diff;
}
} else if( !array_key_exists($key,$array2) || $array2[$key] !== $value ) {
$difference[$key] = $value;
}
}
return $difference;
}
?>
And here an example (note index 'b' in the output):
<?php
$a1=array( 'a' => 0, 'b' => null, 'c' => array( 'd' => null ) );
$a2=array( 'a' => 0, 'b' => null );
var_dump( array_diff_assoc_recursive( $a1, $a2 ) );
var_dump( chinello_array_diff_assoc_recursive( $a1, $a2 ) );
?>
array(1) {
["c"]=>
array(1) {
["d"]=>
NULL
}
}
array(2) {
["b"]=>
NULL
["c"]=>
array(1) {
["d"]=>
NULL
}
}
array_diff_assoc
(PHP 4 >= 4.3.0, PHP 5, PHP 7, PHP 8)
array_diff_assoc — Вычисляет расхождение массивов с дополнительной проверкой индекса
Описание
Сравнивает значения массива array со значениями массивов arrays
и возвращает разницу. В этой функции, в отличие от функции array_diff(),
ключи массива также участвуют в сравнении.
Список параметров
-
array -
Исходный массив
-
arrays -
Массивы для сравнения
Возвращаемые значения
Возвращает массив (array), содержащий значения массива
array, которых нет в других сравниваемых массивах.
Список изменений
| Версия | Описание |
|---|---|
| 8.0.0 | Теперь функцию разрешено вызывать только с одним параметром. Раньше требовалось не менее двух параметров. |
Примеры
Пример #1 Пример использования array_diff_assoc()
В этом примере пара "a" => "green"
содержится в обоих массивах, и поэтому её нет в выводе функции.
Но пара 0 => "red" содержится в выводе функции,
потому что значению "red" в первом массиве автоматически
присваивается ключ 0,
а во втором массиве тому же значению будет присвоен ключ 1,
поскольку ключ 0 уже занят значением yellow.
<?php
$array1 = array("a" => "green", "b" => "brown", "c" => "blue", "red");
$array2 = array("a" => "green", "yellow", "red");
$result = array_diff_assoc($array1, $array2);
print_r($result);
?>Результат выполнения приведённого примера:
Array
(
[b] => brown
[c] => blue
[0] => red
)
Пример #2 Пример использования array_diff_assoc()
Два значения пар key => value
будут расценены как равные только тогда, когда (string) $elem1 === (string)
$elem2. То есть когда строковые представления значений
при строгом сравнении будут тождествеными.
<?php
$array1 = array(0, 1, 2);
$array2 = array("00", "01", "2");
$result = array_diff_assoc($array1, $array2);
print_r($result);
?>Результат выполнения приведённого примера:
Array
(
[0] => 0
[1] => 1
)
Примечания
Замечание: Эта функция проверяет только один уровень n-мерного массива. Сравнить вложенные массивы можно, указав более глубокий уровень, например:
array_diff_assoc($array1[0], $array2[0]);.
Замечание: Необходимо проверять правильный порядок переданных аргументов при сравнении схожих массивов, в которых много ключей. В результирующий массив попадают значения того массива, который идёт первым в списке аргументов.
Смотрите также
- array_diff() - Вычисляет расхождение массивов
- array_diff_uassoc() - Вычисляет расхождение массивов с дополнительной проверкой индекса через пользовательскую callback-функцию
- array_udiff_assoc() - Вычисляет расхождение в массивах с дополнительной проверкой индексов, используя для сравнения значений callback-функцию
- array_udiff_uassoc() - Вычисляет расхождение в массивах с дополнительной проверкой индексов, используя для сравнения значений и индексов callback-функцию
- array_intersect() - Вычисляет пересечение массивов
- array_intersect_assoc() - Вычисляет пересечение массивов с дополнительной проверкой индекса
add a note
User Contributed Notes 21 notes
Giosh ¶
11 years ago
contact at pascalopitz dot com ¶
17 years ago
The direction of the arguments does actually make a difference:
<?php
$a = array(
'x' => 'x',
'y' => 'y',
'z' => 'z',
't' => 't',
);
$b = array(
'x' => 'x',
'y' => 'y',
'z' => 'z',
't' => 't',
'g' => 'g',
);
print_r(array_diff_assoc($a, $b));
print_r(array_diff_assoc($b, $a));
?>
echoes:
Array
(
)
Array
(
[g] => g
)
telefoontoestel at hotmail dot com ¶
10 years ago
an earlier post for recursive array_diff_assoc failed because isset returned false on an array element containing a null value. I updated the code so it compares null values too.
<?php
function array_diff_assoc_recursive($array1, $array2)
{
foreach($array1 as $key => $value)
{
if(is_array($value))
{
if(!isset($array2[$key]))
{
$difference[$key] = $value;
}
elseif(!is_array($array2[$key]))
{
$difference[$key] = $value;
}
else
{
$new_diff = array_diff_assoc_recursive($value, $array2[$key]);
if($new_diff != FALSE)
{
$difference[$key] = $new_diff;
}
}
}
elseif(!array_key_exists($key, $array2) || $array2[$key] != $value)
{
$difference[$key] = $value;
}
}
return !isset($difference) ? 0 : $difference;
}
?>
Michael Richey ¶
11 years ago
If you're looking for a true array_diff_assoc, comparing arrays to determine the difference between two, finding missing values from both, you can use this along with array_merge.
$a = array('a'=>1,'b'=>2,'c'=>3);
$b = array('a'=>1,'b'=>2,'d'=>4);
print_r(array_diff_assoc($a,$b));
// returns:
array
(
[c] => 3
)
print_r(array_diff_assoc($b,$a));
// returns
array
(
[d] => 4
)
print_r(array_merge(array_diff_assoc($a,$b),array_diff_assoc($b,$a)));
// returns
array
(
[c] => 3
[d] => 4
)
chinello at gmail dot com ¶
17 years ago
The following will recursively do an array_diff_assoc, which will calculate differences on a multi-dimensional level. This not display any notices if a key don't exist and if error_reporting is set to E_ALL:
<?php
function array_diff_assoc_recursive($array1, $array2)
{
foreach($array1 as $key => $value)
{
if(is_array($value))
{
if(!isset($array2[$key]))
{
$difference[$key] = $value;
}
elseif(!is_array($array2[$key]))
{
$difference[$key] = $value;
}
else
{
$new_diff = array_diff_assoc_recursive($value, $array2[$key]);
if($new_diff != FALSE)
{
$difference[$key] = $new_diff;
}
}
}
elseif(!isset($array2[$key]) || $array2[$key] != $value)
{
$difference[$key] = $value;
}
}
return !isset($difference) ? 0 : $difference;
}
?>
[NOTE BY danbrown AT php DOT net: This is a combination of efforts from previous notes deleted. Contributors included (Michael Johnson), (jochem AT iamjochem DAWT com), (sc1n AT yahoo DOT com), and (anders DOT carlsson AT mds DOT mdh DOT se).]
dev5er6 at gmail dot com ¶
10 years ago
Works more like the original function:
<?php
function array_diff_assoc_recursive ( )
{
$args = func_get_args ( );
$diff = array ( );
foreach ( array_shift ( $args ) as $key => $val )
{
for ( $i = 0, $j = 0, $tmp = array ( $val ) , $count = count ( $args ); $i < $count; $i++ )
if ( is_array ( $val ) )
if ( !isset ( $args[$i][$key] ) || !is_array ( $args[$i][$key] ) || empty( $args[$i][$key] ) )
$j++;
else
$tmp[] = $args[$i][$key];
elseif ( ! array_key_exists ( $key, $args[$i] ) || $args[$i][$key] !== $val )
$j++;
if ( is_array ( $val ) )
{
$tmp = call_user_func_array ( __FUNCTION__, $tmp );
if ( ! empty ( $tmp ) ) $diff[$key] = $tmp;
elseif ( $j == $count ) $diff[$key] = $val;
}
elseif ( $j == $count && $count ) $diff[$key] = $val;
}
return $diff;
}
?>
tero dot lahtinen at iki dot fi ¶
7 years ago
array_diff_assoc will fail, if a value is something that can not be converted to a string.
benjamin at moonfactory dot co dot jp ¶
19 years ago
Hi all,
For php versions < 4.3...
<?php
/**
* array_diff_assoc for version < 4.3
**/
if (!function_exists('array_diff_assoc'))
{
function array_diff_assoc($a1, $a2)
{
foreach($a1 as $key => $value)
{
if(isset($a2[$key]))
{
if((string) $value !== (string) $a2[$key])
{
$r[$key] = $value;
}
}else
{
$r[$key] = $value;
}
}
return $r ;
}
}
?>
Alexander Podgorny ¶
18 years ago
NOTE: the diff_array also removes all the duplicate values that match to the values in the second array:
<?php
$array1 = array("a","b","c","a","a");
$array2 = array("a");
$diff = array_diff($array1,$array2);
// yields: array("b","c") the duplicate "a" values are removed
?>
carl at thep dot lu dot se ¶
21 years ago
To unset elements in an array if you know the keys but not the values, you can do:
<?php
$a = array("foo", "bar", "baz", "quux");
$b = array(1, 3); // Elements to get rid of
foreach($b as $e)
unset($a[$e]);
?>
Of course this makes most sense if $b has many elements or is dynamically generated.
news_yodpeirs at thoftware dot de ¶
13 years ago
A quite simple (yet not very efficient) way to compare the first level of arrays which have values that are not strings:
array_map('unserialize',array_diff_assoc(array_map('serialize',$arr1),array_map('serialize',$arr2)))
Might be useful for debugging (that's what I use it for).
jrajpu10 at gmail dot com ¶
16 years ago
array_diff_assoc can also be used to find the duplicates in an array
<?php
$arr = array('1','2','3','4','3','2','5');
$uniques = array_unique($arr);
// array_diff will not work here, array_diff_assoc works as it takes the key // in account.
$dups = array_diff_assoc($arr, $uniques);
print_r($dups);
?>
Note: The index of the $dups is not in strict sequential order as expected by C programmer.
cedric at daneel dot net ¶
17 years ago
To diff between n-dimensional array, juste use this :
<?php
function array_diff_values($tab1, $tab2)
{
$result = array();
foreach($tab1 as $values) if(! in_array($values, $tab2)) $result[] = $values;
return $result;
}
?>
spark dot crz at gmail dot com ¶
6 years ago
Recursive implementation accepting multiple n-level-arrays as parameters:
<?php
function recursiveDiff() {
$arrs = func_get_args();
$first = array_shift($arrs);
$diff = [];
foreach($first as $key => $value) {
$values = array_map(function($arr) use($key){
if (is_array($arr) && !array_key_exists($key, $arr))
return null;
return $arr[$key];
}, $arrs);
if (in_array($value, $values))
continue;
if (is_array($value)) {
array_unshift($values, $value);
$diff[$key] = call_user_func_array(__FUNCTION__, $values);
continue;
}
$diff[$key] = $first[$key];
}
return $diff;
}
?>
The other attempt was cleaner but didn't work for all cases.
Henry ¶
10 months ago
function array_diff_assoc_recursive($array1, $array2)
{
$array1Array = [];
foreach ($array1 as $key => $value) {
if (!is_array($value)) {
continue;
}
$array1Array[$key] = $value;
unset($array1[$key]);
}
$array2Array = [];
foreach ($array2 as $key => $value) {
if (!is_array($value)) {
continue;
}
$array2Array[$key] = $value;
unset($array2[$key]);
}
$diff = is_int(array_key_first($array1)) ? array_values(array_diff($array1, $array2)) : array_diff_assoc($array1, $array2);
foreach ($array1Array as $key => $value) {
if (isset($array2Array[$key])) {
$subDiff = array_diff_assoc_recursive($value, $array2Array[$key]);
if (count($subDiff) !== 0) {
$diff = array_merge($diff, is_int($key) ? [$subDiff] : [$key => $subDiff]);
}
} else {
$diff = array_merge($diff, is_int($key) ? [$value] : [$key => $value]);
}
}
return $diff;
}
folurinyinka at gmail dot com ¶
2 years ago
Recursive implementation accepting multiple n-level-arrays as parameters:
```php
function recursiveDiff(...$arrays)
{
$first = array_shift($arrays);
$diff = [];
foreach ($first as $key => $value) {
$values = array_map(function ($arr) use ($key) {
if (is_array($arr) && !array_key_exists($key, $arr)) {
return null;
}
return isset($arr[$key]) ? $arr[$key] : null;
}, $arrs);
if (in_array($value, $values)) {
continue;
}
if (is_array($value)) {
array_unshift($values, $value);
$diff[$key] = call_user_func_array(__FUNCTION__, $values);
continue;
}
$diff[$key] = $first[$key];
}
return $diff;
}
```
angujomondi at gmail dot com ¶
3 years ago
For recursive diff of multiple arrays, exending solution provided by Gosh.
<?php
function array_diff_assoc_recursive(array $array, array ...$arrays)
{
$func = function($array1, $array2) use (&$func){
$difference = [];
foreach ($array1 as $key => $value) {
if (is_array($value)) {
if (!isset($array2[$key]) || !is_array($array2[$key])) {
$difference[$key] = $value;
} else {
$new_diff = $func($value, $array2[$key]);
if (!empty($new_diff)) {
$difference[$key] = $new_diff;
}
}
} else {
if (!array_key_exists($key, $array2) || $array2[$key] !== $value) {
$difference[$key] = $value;
}
}
}
return $difference;
};
$diffs = $array;
foreach ($arrays as $_array) {
$diffs = $func($diffs, $_array);
}
return $diffs;
}
?>
nekto ¶
2 years ago
PHP associative keys are case-sensitive, key "a" is different from key "A":
<?php
$arr = ["A" => 666];
var_dump($arr["a"]);
var_dump($arr["A"]);
?>
produces:
NULL
int(666)
And in the same way, array_diff_assoc treats keys case-sensitively, and key "A" is not equal to key "a" and will be diffed:
<?php
// in arrays below value of "a" and "A" are the same, but keys are different
// values of "b" are different
// values of "c" are the same
$compareWhat = ["a" => 666, "b" => 666, "c" => 666, ];
$compareWith = ["A" => 666, "b" => 667, "c" => 666, ];
var_dump(array_diff_assoc($compareWhat, $compareWith));
?>
produces:
array(2) {
["a"]=> int(666)
["b"]=> int(666)
}
And if the order of values in array is different, the order of the result will be different, although essentially the result stays the same:
<?php
// the same as above, but "b" comes before "a" in $compareWhat
$compareWhat = ["b" => 666, "a" => 666, "c" => 666, ];
$compareWith = ["A" => 666, "b" => 667, "c" => 666, ];
var_dump(array_diff_assoc($compareWhat, $compareWith));
?>
produces:
array(2) {
["b"]=> int(666)
["a"]=> int(666)
}
shadow_games at abv dot bg ¶
10 years ago
there is a functiont that i searched long enough now i have created it so someone else to find it if he need it ;]
<?php
function compare_two_object_recursive($object_1, $object_2, $object_1_Identifier = false, $object_2_Identifier = false){
$object1 = (array)$object_1;
$object2 = (array)$object_2;
$object3 = array();
$o1i = $object_1_Identifier ? $object_1_Identifier : 1;
$o2i = $object_2_Identifier ? $object_2_Identifier : 2;
foreach($object1 as $key => $value){
if(is_object($object1[$key])){
$object1[$key] = (array)$object1[$key];
$object2[$key] = (array)$object2[$key];
$object3[$key] = (object)compare_two_object_recursive($object1[$key], $object2[$key], $o1i, $o2i);
}elseif(is_array($object1[$key])){
$object3[$key] = compare_two_object_recursive($object1[$key], $object2[$key], $o1i, $o2i);
}else{
if($object1[$key] == $object2[$key]){
$object3[$key]['comparison_status'] = "SAME";
}else{
$object3[$key]['comparison_status'] = "NOT THE SAME";
$object3[$key][$o1i] = $object1[$key];
$object3[$key][$o2i] = $object2[$key];
}
}
}
return $object3;
}
?>
spark dot crz at gmail dot com ¶
6 years ago
Yet another recursive implementation, without if-else hell and with multiple parameters just like the original.
<?php
function recursiveDiff() {
$arrs = func_get_args();
$diff = call_user_func_array('array_diff_assoc', $arrs);
foreach($diff as $key => $value) {
if (!is_array($value))
continue;
$children = array_map(function($arr) use($key){
return $arr[$key];
}, $arrs);
$diff[$key] = call_user_func_array(__FUNCTION__, $children);
}
return $diff;
}
francois-php at ceonizme dot fr ¶
10 years ago
to chinello at gmail dot com
I've had to use your function but it showed that the use of isset can't differentiate the NULL values from not setted values.
Here's a version that takes care of this subtility.
<?php
function array_diff_assoc_recursive($array1, $array2)
{
$difference = NULL;
foreach($array1 as $key => $value)
{
if(is_array($value))
{
if(!array_key_exists($key, $array2))
{
$difference[$key] = $value;
}
elseif(!is_array($array2[$key]))
{
$difference[$key] = $value;
}
else
{
$new_diff = array_diff_assoc_recursive($value, $array2[$key]);
if($new_diff != FALSE)
{
$difference[$key] = $new_diff;
}
}
}
elseif(!array_key_exists($key, $array2) || $array2[$key] != $value)
{
$difference[$key] = $value;
}
}
return !isset($difference) ? 0 : $difference;
}
?>
Hope that helps
François
