Try this to know behavior:
<?php
function resource_test($resource, $name) {
echo
'[' . $name. ']',
PHP_EOL,
'(bool)$resource => ',
$resource ? 'TRUE' : 'FALSE',
PHP_EOL,
'get_resource_type($resource) => ',
get_resource_type($resource) ?: 'FALSE',
PHP_EOL,
'is_resoruce($resource) => ',
is_resource($resource) ? 'TRUE' : 'FALSE',
PHP_EOL,
PHP_EOL
;
}
$resource = tmpfile();
resource_test($resource, 'Check Valid Resource');
fclose($resource);
resource_test($resource, 'Check Released Resource');
$resource = null;
resource_test($resource, 'Check NULL');
?>
It will be shown as...
[Check Valid Resource]
(bool)$resource => TRUE
get_resource_type($resource) => stream
is_resoruce($resource) => TRUE
[Check Released Resource]
(bool)$resource => TRUE
get_resource_type($resource) => Unknown
is_resoruce($resource) => FALSE
[Check NULL]
(bool)$resource => FALSE
get_resource_type($resource) => FALSE
Warning: get_resource_type() expects parameter 1 to be resource, null given in ... on line 10
is_resoruce($resource) => FALSE
get_resource_type
(PHP 4 >= 4.0.2, PHP 5, PHP 7, PHP 8)
get_resource_type — Returns the resource type
Description
This function gets the type of the given resource.
Parameters
-
resource -
The evaluated resource handle.
Return Values
If the given resource is a resource, this function
will return a string representing its type. If the type is not identified
by this function, the return value will be the string
Unknown.
This function will return null and generate an error if
resource is not a resource.
Examples
Example #1 get_resource_type() example
<?php
$fp = fopen("foo", "w");
echo get_resource_type($fp) . "\n";
// As of PHP 8.0.0, the following does not work anymore. The curl_init function returns a CurlHandle object now.
$c = curl_init();
echo get_resource_type($c) . "\n";
?>Output of the above example in PHP 7:
stream curl
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User Contributed Notes 1 note
CertaiN ¶
10 years ago
