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<ResourcePseudo-types used in this documentation>
Last updated: Tue, 19 Sep 2006

NULL

The special NULL value represents that a variable has no value. NULL is the only possible value of type NULL.

Note: The null type was introduced in PHP 4.

A variable is considered to be NULL if

  • it has been assigned the constant NULL.

  • it has not been set to any value yet.

  • it has been unset().

Syntax

There is only one value of type NULL, and that is the case-insensitive keyword NULL.

<?php
$var = NULL;       
?>

See also is_null() and unset().




<ResourcePseudo-types used in this documentation>
Last updated: Tue, 19 Sep 2006