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array_diff_assoc

(PHP 4 >= 4.3.0, PHP 5, PHP 7)

array_diff_assocComputes the difference of arrays with additional index check

Description

array_diff_assoc ( array $array , array ...$arrays ) : array

Compares array against arrays and returns the difference. Unlike array_diff() the array keys are also used in the comparison.

Parameters

array

The array to compare from

arrays

Arrays to compare against

Return Values

Returns an array containing all the values from array 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(0, 1, 2);
$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() - Computes the difference of arrays
  • array_diff_uassoc() - Computes the difference of arrays with additional index check which is performed by a user supplied callback function
  • array_udiff_assoc() - Computes the difference of arrays with additional index check, compares data by a callback function
  • array_udiff_uassoc() - Computes the difference of arrays with additional index check, compares data and indexes by a callback function
  • array_intersect() - Computes the intersection of arrays
  • array_intersect_assoc() - Computes the intersection of arrays with additional index check

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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.array-diff-assoc.php