PHP | SplObjectStorage unserialize() Function

The SplObjectStorage::unserialize() function is an inbuilt function in PHP which is used to unserialize the storage from its serialize string representation.

Syntax:

void SplObjectStorage::unserialize( $serilize )

Parameters: This function accepts a single parameter $serialize which specifies the string serialization of the storage.

Return Value: This function does not return any value.

Below programs illustrate the SplObjectStorage::unserialize() function in PHP:

Program 1:

<?php

$obj1 = new StdClass;

// Create an empty SplObjectStorage
$gfg1 = new SplObjectStorage();
$gfg1[$obj1] = "Geeks";

// Use unserialize() function
$gfg1->unserialize($gfg1->serialize());
print_r($gfg1);

?>

Output:

SplObjectStorage Object
(
    [storage:SplObjectStorage:private] => Array
        (
            [00000000494fcd4d000000001f544823] => Array
                (
                    [obj] => stdClass Object
                        (
                        )

                    [inf] => Geeks
                )

            [00000000494fcd4f000000001f544823] => Array
                (
                    [obj] => stdClass Object
                        (
                        )

                    [inf] => Geeks
                )

        )

)

Program 2:

<?php

$obj1 = new StdClass;
$obj2 = new StdClass;

// Create an empty SplObjectStorage
$gfg1 = new SplObjectStorage();
$gfg1[$obj1] = "Geeks";

// Create an empty SplObjectStorage
$gfg2 = new SplObjectStorage();
$gfg2[$obj1] = "GFG";
$gfg2[$obj2] = "GeeksClasses";

// Use unserialize() function
$gfg1->unserialize($gfg2->serialize());
var_dump(count($gfg1));

// Use unserialize() function
$gfg2->unserialize($gfg1->serialize());
var_dump(count($gfg2));
?>

Output:

int(3)
int(5)

Reference: https://www.php.net/manual/en/splobjectstorage.unserialize.php