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ArrayObject> <SPL Functions
Last updated: Fri, 21 Nov 2008

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spl_object_hash

(PHP 5 >= 5.2.0)

spl_object_hash Return hash id for given object

Description

string spl_object_hash ( object $obj )

This function returns an unique identifier for the object. This id can be used as a hash key for storing objects or for identifying an object.

Parameters

object

Any object.

Return Values

A string that is unique for each object and is always the same for the same object.

Examples

Example #1 A spl_object_hash() example

<?php
$id 
spl_object_hash($object);
$storage[$id] = $object;
?>



add a note add a note User Contributed Notes
spl_object_hash
planetbeing
05-Jul-2007 04:40
Note that the contents (properties) of the object are NOT hashed by the function, merely its internal handle and handler table pointer. This is sufficient to guarantee that any two objects simultaneously co-residing in memory will have different hashes. Uniqueness is not guaranteed between objects that did not reside in memory simultaneously, for example:

var_dump(spl_object_hash(new stdClass()), spl_object_hash(new stdClass()));

Running this alone will usually generate the same hashes, since PHP reuses the internal handle for the first stdClass after it has been dereferenced and destroyed when it creates the second stdClass.

ArrayObject> <SPL Functions
Last updated: Fri, 21 Nov 2008
 
 
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