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PHP Tutorial

PHP: is_null() function

Description

The is_null () function is used to test whether a variable is NULL or not.

Version:

(PHP 4 and above)

Syntax:

is_null (var_name)

Parameter:

Name Description Required /
Optional
Type
var_name The variable being checked Required Mixed*

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

Return value:

Returns TRUE if var_name is null, FALSE otherwise.

Value Type: Boolean

Example:

<?php
$var_name = TRUE;
if (is_null($var_name))
{
echo 'Variable is  NULL';
}
else
{
echo 'Variable is not NULL';
}
?>

Output:

Variable is not NULL

View the example in the browser

Practice here online:

See also

PHP Function Reference

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