PHP: array_diff_assoc function - 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]);.

array_diff_assoc

Description

Parameters

Return Values

Examples

Notes

See Also