php / 8.1.5 / function.is-resource.html /

is_resource

(PHP 4, PHP 5, PHP 7, PHP 8)

is_resource Finds whether a variable is a resource

Description

is_resource(mixed $value): bool

Finds whether the given variable is a resource.

Parameters

value

The variable being evaluated.

Return Values

Returns true if value is a resource, false otherwise.

Examples

Example #1 is_resource() example

<?php

$db_link = @mysql_connect('localhost', 'mysql_user', 'mysql_pass');
if (!is_resource($db_link)) {
    die('Can\'t connect : ' . mysql_error());
}

?>

Notes

Note:

is_resource() is not a strict type-checking method: it will return false if value is a resource variable that has been closed.

See Also

© 1997–2021 The PHP Documentation Group
Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.is-resource.php