(PHP 4 >= 4.0.4, PHP 5, PHP 7)
is_null — Finds whether a variable is null
is_null ( mixed $var ) : bool
Finds whether the given variable is null
.
var
The variable being evaluated.
Returns true
if var
is null, false
otherwise.
Example #1 is_null() example
<?php error_reporting(E_ALL); $foo = NULL; var_dump(is_null($inexistent), is_null($foo)); ?>
Notice: Undefined variable: inexistent in ... bool(true) bool(true)
null
type
© 1997–2020 The PHP Documentation Group
Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.is-null.php