is_null
(PHP 4 >= 4.0.4, PHP 5, PHP 7, PHP 8)
is_null —
Finds whether a variable is null
Description
is_null(
mixed $value
):
bool
Parameters
-
value
-
The variable being evaluated.
Return Values
Returns true
if value
is null, false
otherwise.
Examples
Example #1 is_null() example
<?phperror_reporting(E_ALL);$foo = NULL;var_dump(is_null($inexistent), is_null($foo));?>
Notice: Undefined variable: inexistent in ...
bool(true)
bool(true)
See Also
- The
null
type
- isset() - Determine if a variable is declared and is different than 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