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PHP - Manual: get_resource_type

2024-12-22

get_resource_type

(PHP 4 >= 4.0.2, PHP 5, PHP 7, PHP 8)

get_resource_type 返回资源(resource)类型

描述

get_resource_type(resource $handle): string

此函数返回一个字符串,用于表示传递给它的 resource 的类型。如果参数不是合法的 resource,将产生错误。

<?php
$c 
mysql_connect();
echo 
get_resource_type($c)."\n";
// 打印:mysql link

$fp fopen("foo","w");
echo 
get_resource_type($fp)."\n";
// 打印:file

$doc new_xmldoc("1.0");
echo 
get_resource_type($doc->doc)."\n";
// 打印:domxml document
?>
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User Contributed Notes 1 note

up
13
CertaiN
8 years ago
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

官方地址:https://www.php.net/manual/en/function.get-resource-type.php

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