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PHP Manual for

array_intersect

(PHP 4 >= 4.0.1)

array_intersect -- Computes the intersection of arrays

Description

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

array_intersect() returns an array containing all the values of array1 that are present in all the arguments. Note that keys are preserved.

Example 1. array_intersect() example


<?php
$array1 = array("a" => "green", "red", "blue");
$array2 = array("b" => "green", "yellow", "red");
$result = array_intersect($array1, $array2);
?>

This makes $result have


Array
(
    [a] => green
    [0] => red
)

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