The is_resource Function
The is_resource function checks if the passed variable is a resource. A resource is a special data type in PHP that references external resources, such as files, database connections, etc. The function returns true if the variable is a resource, and false otherwise.
Syntax
is_resource(mixed $var): bool
Example
Let's check if a variable is a resource:
<?php
$file = fopen('test.txt', 'r');
$res = is_resource($file);
var_dump($res);
fclose($file);
?>
Code execution result:
true
Example
Let's check a regular variable:
<?php
$var = 'hello';
$res = is_resource($var);
var_dump($res);
?>
Code execution result:
false
Example
Let's check a closed resource:
<?php
$file = fopen('test.txt', 'r');
fclose($file);
$res = is_resource($file);
var_dump($res);
?>
Code execution result:
false
