PHP is_null() Function
❮ PHP Variable Handling Reference
Example
Check whether a variable is NULL or not:
<?php
$a = 0;
echo "a is " . is_null($a) . "<br>";
$b = null;
echo "b
is " . is_null($b) . "<br>";
$c = "null";
echo "c is " . is_null($c)
. "<br>";
$d = NULL;
echo "d is " . is_null($d) . "<br>";
?>
Try it Yourself »
Definition and Usage
The is_null() function checks whether a variable is NULL or not.
This function returns true (1) if the variable is NULL, otherwise it returns false/nothing.
Syntax
is_null(variable);
Parameter Values
Parameter | Description |
---|---|
variable | Required. Specifies the variable to check |
Technical Details
Return Value: | TRUE if variable is NULL, FALSE otherwise |
---|---|
Return Type: | Boolean |
PHP Version: | 4.0.4+ |
❮ PHP Variable Handling Reference