PHP Manual: array_diff_assoc


Enter the keyword for better results

array_diff_assoc

(PHP 4 >= 4.3.0, PHP 5)

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 used in the comparision.

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 ouput from the function. Unlike this, the pair 0 => "red" is in the ouput 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]);.