array_diff_assoc

Computes the difference of arrays with additional index check

Description

array array_diff_assoc ( array $array1 , array $array2 [, array $... ] )

Compares array1 against array2 and returns the difference. Unlike array_diff the array keys are also used in the comparison.

Parameters

array1

The array to compare from

array2

An array to compare against

...

More arrays to compare against

Return Values

Returns an array containing all the values from array1 that are not present in any of the other arrays.

Examples

Example #1 array_diff_assoc example

In this example you see the "a" => "green" pair is present in both arrays and thus it is not in the output from the function. Unlike this, the pair 0 => "red" is in the output because in the second argument "red" has key which is 1.

<?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);
?>

The above example will output:

Array
(
    [b] => brown
    [c] => blue
    [0] => red
)

Example #2 array_diff_assoc example

Two values from key => value pairs are considered equal only if (string) $elem1 === (string) $elem2 . In other words a strict check takes place so the string representations must be the same.

<?php
$array1 
= array(012);
$array2 = array("00""01""2");
$result array_diff_assoc($array1$array2);
print_r($result);
?>

The above example will output:

Array
(
    [0] => 0
    [1] => 1
    )

Notes

Note: This function only checks one dimension of a n-dimensional array. Of course you can check deeper dimensions by using, for example, array_diff_assoc($array1[0], $array2[0]);.

Note: Ensure you pass arguments in the correct order when comparing similar arrays with more keys. The new array should be the first in the list.

See Also

  • array_diff
  • array_diff_uassoc
  • array_udiff_assoc
  • array_udiff_uassoc
  • array_intersect
  • array_intersect_assoc