is_null
(PHP 4 >= 4.0.4, PHP 5, PHP 7)
is_null — Finds whether a variable is NULL
Description
bool is_null ( mixed $var ) Finds whether the given variable is NULL.
Parameters
var
The variable being evaluated.
Return Values
Returns TRUE if var is null, FALSE otherwise.
Examples
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)See Also
- The
NULLtype
- isset() - Determine if a variable is set and is not NULL
- is_bool() - Finds out whether a variable is a boolean
- is_numeric() - Finds whether a variable is a number or a numeric string
- is_float() - Finds whether the type of a variable is float
- is_int() - Find whether the type of a variable is integer
- is_string() - Find whether the type of a variable is string
- is_object() - Finds whether a variable is an object
- is_array() - Finds whether a variable is an array
← is_long
is_numeric →
? 1997–2017 The PHP Documentation GroupLicensed under the Creative Commons Attribution License v3.0 or later.
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