# array_search

(PHP 4 >= 4.0.5, PHP 5)

array_search — Searches the array for a given value and returns the corresponding key if successful

### Description

mixed array_search ( mixed `$needle` , array `$haystack` [, bool `$strict` ] )

Searches `haystack` for `needle` and returns the key if it is found in the array, `FALSE` otherwise.

> Note: If `needle` is a string, the comparison is done in a case-sensitive manner.

> Note: Prior to PHP 4.2.0, array_search() returns `NULL` on failure instead of `FALSE`.

If the optional third parameter `strict` is set to `TRUE` then the array_search() will also check the types of the `needle` in the `haystack` .

If `needle` is found in `haystack` more than once, the first matching key is returned. To return the keys for all matching values, use array_keys() with the optional `search_value` parameter instead.

Example#1 array_search() example

`<?php
$array = array(0 => 'blue', 1 => 'red', 2 => 'green', 3 => 'red');
$key = array_search('green', $array); // $key = 2;
$key = array_search('red', $array); // $key = 1;
?>`
Warning

This function may return Boolean `FALSE`, but may also return a non-Boolean value which evaluates to `FALSE`, such as 0 or "". Please read the section on Booleans for more information. Use the === operator for testing the return value of this function.

See also array_keys(), array_values(), array_key_exists(), and in_array().