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PHP key() Function

PHP Array Reference Complete PHP Array Reference

Definition and Usage

The key() function returns the element key from the current internal pointer position.

This function returns FALSE on error.

Syntax

key(array)

Parameter Description
array Required. Specifies the array to use

Example

<?php
$people = array("Peter", "Joe", "Glenn", "Cleveland");
echo "The key from the current position is: " . key($people);
?>

The output of the code above will be:

The key from the current position is: 0

PHP Array Reference Complete PHP Array Reference

From http://www.w3schools.com (Copyright Refsnes Data)