NuSphere Corporation
Support Services
Overview
KB
PHP Manual
CSS2 Manual
HTML Manual
JS Guide
JS Reference
Technical FAQ
PhpDock Manual
Nu-Coder Manual
PhpExpress Manual
PHP Joomla Development
Learn PHP
<array_key_existsarray_map>
Last updated: Tue, 19 Sep 2006

array_keys

(PHP 4, PHP 5)

array_keys -- Return all the keys of an array

Description

array array_keys ( array input [, mixed search_value [, bool strict]] )

array_keys() returns the keys, numeric and string, from the input array.

If the optional search_value is specified, then only the keys for that value are returned. Otherwise, all the keys from the input are returned. As of PHP 5, you can use strict parameter for comparison including type (===).

Example 1. array_keys() example

<?php
$array = array(0 => 100, "color" => "red");
print_r(array_keys($array));

$array = array("blue", "red", "green", "blue", "blue");
print_r(array_keys($array, "blue"));

$array = array("color" => array("blue", "red", "green"),
               "size"  => array("small", "medium", "large"));
print_r(array_keys($array));
?>

The above example will output:

Array
(
    [0] => 0
    [1] => color
)
Array
(
    [0] => 0
    [1] => 3
    [2] => 4
)
Array
(
    [0] => color
    [1] => size
)

See also array_values() and array_key_exists().




<array_key_existsarray_map>
Last updated: Tue, 19 Sep 2006