PHP: unset() function

Last update on August 19 2022 21:50:40 (UTC/GMT +8 hours)

Description

The unset() function destroys a given variable.

Version:

(PHP 4 and above)

Syntax:

unset (var1, var2.... )

Parameters:

Name	Description	Required / Optional	Type
var1	The variable to be unset.	Required	Mixed*
var2	Another variable to be unset	Optional	Mixed*

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

Return value:

No value is returned.

Example - 1:

<?php
$xyz='w3resource.com';
echo 'Before using unset() the value of $xys is : '. $xyz.'<br>';
unset($xyz);
echo 'After using unset() the value of $xys is : '. $xyz;
?>

Output :

Before using unset() the value of $xys is : w3resource.com
After   using unset() the value of $xys is :

View the example in the browser

Practice here online :

Example - 2 :

<?php
function destroy_variable()
{
unset($GLOBALS['w3resource']);
}
$w3resource='Php Tutorial';
destroy_variable();
echo $w3resource;
?>

View the example in the browser

See also

PHP Function Reference

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