(PHP 8)
get_resource_id — Returns an integer identifier for the given resource
$resource): intThis function provides a type-safe way for generating the integer identifier for a resource.
resourceThe evaluated resource handle.
The int identifier for the given resource.
This function is essentially an int cast of
resource to make it easier to retrieve the resource ID.
示例 #1 get_resource_id() produces the same result as an int cast
<?php
$handle = fopen("php://stdout", "w");
echo (int) $handle . "\n";
echo get_resource_id($handle);
?>以上示例的输出类似于：
698 698