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is_resource

is_resource

(PHP 4, PHP 5, PHP 7)

is_resource — Finds whether a variable is a resource

Description

bool is_resource ( mixed $var )

Finds whether the given variable is a resource.

Parameters

var

The variable being evaluated.

Return Values

Returns TRUE if var 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 var is a resource variable that has been closed.

See Also

  • The resource-type documentation

  • get_resource_type() - Returns the resource type

← is_real

is_scalar →

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Licensed under the Creative Commons Attribution License v3.0 or later.

https://secure.php.net/manual/en/function.is-resource.php