Find the difference from two arrays in php - php

Question

--$arr1----
Array
(
[0] => Array
(
[id] => 1
[Name] => AAA
)
[1] => Array
(
[id] => 6
[Name] => BBB
)
)
--$arr2---
Array
(
[0] => Array
(
[id] => 1
[Name] => AAA
)
[1] => Array
(
[id] => 6
[Name] => BBB
)
[2] => Array
(
[id] => 46
[Name] => CCC
)
)
I would like the final result as following. Is there anyone can help me?
--Final Result--
Array
(
[0] => Array
(
[id] => 46
[Name] => CCC
)
)
UPDATE---
In this case, the result of array_diff($arr1,$arr2) is empty.

Answer 1

The easiest way is Mark Baker's solution or just write your own simple function:
Code:
function arrdiff($a1, $a2) {
$res = array();
foreach($a2 as $a) if (array_search($a, $a1) === false) $res[] = $a;
return $res;
}
print_r(arrdiff($arr1, $arr2));
Output:
Array
(
[0] => Array
(
[id] => 46
[name] => CCC
)
)

Answer 2

$arr1 = array(array('id' => 1, 'Name' => 'AAA'),
array('id' => 6, 'Name' => 'BBB')
);
$arr2 = array(array('id' => 1, 'Name' => 'AAA'),
array('id' => 6, 'Name' => 'BBB'),
array('id' => 46, 'Name' => 'CCC')
);
$results = array_diff(array_map('serialize',$arr2),array_map('serialize',$arr1));
$results = array_map('unserialize',$results);
var_dump($results);
EDIT
And just for the sheer fun of it, you could use array_filter() instead of array_diff() - which means no need to serialize anything at all
$results = array_filter($arr2, function ($value) use($arr1) { return !in_array($value,$arr1); } );
var_dump($results);

Answer 3

You should use array_diff():
$finalResult = array_diff($arr2, $arr1);
If you need more complex comparison you may also build foreach loop and use like this:
function compareItems( $a, $b){
return $a['id'] == $b['id']; // Example compare criteria
}
$result = array();
foreach( $arr1 as $item){
foreach( $arr2 as $key => $it){
if( !compareItems( $item, $it)){
$result[] = $it; // Either build new array
unset( $arr2[$key]); // Or remove items from original array
break;
}
}
}
And than you'll probably want to implement the same with reversed order of $arr1 and $arr2.

Answer 4

You can solve this with array_udiff()
function arr_comp($a, $b)
{
if ($a['id'] == $b['id'])
return 0;
else if ($a['id'] > $b['id'])
return 1;
else
return -1;
}
$result = array_udiff($arr2, $arr1, 'arr_comp');
or if you don't know in which array the differences may be you can try:
$res1 = array_udiff($arr1, $arr2, 'arr_comp');
$res2 = array_udiff($arr2, $arr1, 'arr_comp');
$result = array_merge($res1, $res2);

Answer 5

$arrDif=array();
$i=0;
foreach($arr1 as $value)
{
if(!in_array($value, $arr2))
{
$arrDif[$i]=$value;
$i++;
}
}

Answer 6

Take a look at the PHP built-in function array_diff. That'll help you out :-) Just pass your two arrays, and store the array returned by array_diff(), which will contain the differences between the two arrays.
As you're using multi-dimensional arrays, look at this comment on the PHP website: http://www.php.net/manual/en/function.array-diff.php#98680.