PHP: is_null() function
Description
The is_null () function is used to test whether a variable is NULL or not.
Version:
(PHP 4 and above)
Syntax:
is_null (var_name)
Parameter:
| Name | Description | Required / Optional |
Type |
|---|---|---|---|
| var_name | The variable being checked | Required | Mixed* |
*Mixed: Mixed indicates that a parameter may accept multiple (but not necessarily all) types.
Return value:
Returns TRUE if var_name is null, FALSE otherwise.
Value Type: Boolean
Example:
<?php
$var_name = TRUE;
if (is_null($var_name))
{
echo 'Variable is NULL';
}
else
{
echo 'Variable is not NULL';
}
?>
Output:
Variable is not NULL
View the example in the browser
Practice here online:
See also
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