(PHP 4 )

array_diff -- Computes the difference of arrays


array array_diff (array array1, array array2 [, array ...])

array_diff() returns an array containing all the values of array1 that are not present in any of the other arguments. Note that keys are preserved.

Example 1. array_diff() example

$array1 = array ("a" => "green", "red", "blue", "red");
$array2 = array ("b" => "green", "yellow", "red");
$result = array_diff ($array1, $array2);

This makes $result have array ("blue");. Multiple occurences in $array1 are all treated the same way.

Note: Two elements are considered equal if and only if (string) $elem1 === (string) $elem2. In words: when the string representation is the same.


This was broken in PHP 4.0.4!

See also array_intersect().