note 101644 deleted from function.call-user-func-array by danbrown
| From: | danbrown@php.net | Date: | Sat, 01 Jan 2011 00:46:08 +0000 |
| Subject: | note 101644 deleted from function.call-user-func-array by danbrown | ||
| References: | 1 | Groups: | php.notes |
| Request: | Send a blank email to php-notes+get-175383@lists.php.net to get a copy of this message | ||
Note Submitter: jpadvo at gmail dot com
----
With a bit of magic, you can use call_user_func_array to call an objects constructor -- even if it
has required arguments. This can be a very useful trick in a factory class.
<?php
// First, create an empty, vanilla stdClass object
$object = (object) array( );
// Then change it to the class you want. Notice that we have created a
// $classname object without calling $classname->__construct() !
$this->changeClass( $object, $classname );
// Now you can call the constructor, with all the required arguments in place. Bam!
$result = call_user_func_array( array( $object, "__construct" ), $args );
// changeClass is adapted from the example at:
// http://www.jasny.net/articles/a-dark-corner-of-php-class-casting/
function changeClass(&$obj, $newClass)
{
$obj = unserialize(preg_replace // change object into type $new_class
( "/^O:[0-9]+:\"[^\"]+\":/i",
"O:".strlen($newClass).":\"".$newClass."\":",
serialize($obj)
));
}
?>