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PHP: key() function

PHP: Fetch a key from an array

The key() function is used to get the index element of the current array position.

Version:

(PHP 4 and above)

Syntax:

key(array_name) 

Parameter:

Name Description Required /
Optional
Type
array_name Array to use. Required Array

Return value:

The key of the current array element

Value Type : Mixed*.

*Mixed : Mixed indicates that a parameter may accept multiple (but not necessarily all) types.

Example:

<?php
$subjects = array("Subject1" => "Physics", "Subject2" => "Chemistry", "Subject3" => "Biology");
echo "Current position Key is : " . key($subjects);
?> 

Output:

Current position Key is: Subject1

Pictorial Presentation:

php function reference: key() function

View the example in the browser

Practice here online:

See also

PHP Function Reference

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