NULL
NULL
The special NULL value represents a variable with no value. NULL is the only possible value of type null.
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 constant NULL.
<?php $var = NULL; ?>
Casting to NULL
Warning
This feature has been DEPRECATED as of PHP 7.2.0. Relying on this feature is highly discouraged.
Casting a variable to null using (unset) $var will not remove the variable or unset its value. It will only return a NULL value.
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Licensed under the Creative Commons Attribution License v3.0 or later.
https://secure.php.net/manual/en/language.types.null.php
