Using array_diff_assoc() to Compute Array Differences with Index Checks in PHP

The PHP function array_diff_assoc() returns an array containing values from the first array that are not present in any of the subsequent arrays, comparing both keys and values.

Parameters: array1 (required) – the array to compare against; array2 (required) – the array to compare with; additional optional arrays array3, … can be provided.

Return value: an array of the differing key‑value pairs from array1.

Example:

<?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);
?>

Output:

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