unserialize

Description

unserialize() takes a single serialized variable (see serialize()) and converts it back into a PHP value. The converted value is returned, and can be a boolean, integer, float, string, array or object. In case the passed string is not unserializeable, FALSE is returned and E_NOTICE is issued.

If the variable being unserialized is an object, after successfully reconstructing the object PHP will automatically attempt to call the __wakeup() member function (if it exists).

Example 1. unserialize_callback_func example <?php $serialized_object='O:1:"a":1:{s:5:"value";s:3:"100";}'; // unserialize_callback_func directive available as of PHP 4.2.0 ini_set('unserialize_callback_func', 'mycallback'); // set your callback_function function mycallback($classname) {     // just include a file containing your classdefinition     // you get $classname to figure out which classdefinition is required } ?>

Example 2. unserialize() example <?php // Here, we use unserialize() to load session data to the // $session_data array from the string selected from a database. // This example complements the one described with serialize(). $conn = odbc_connect("webdb", "php", "chicken"); $stmt = odbc_prepare($conn, "SELECT data FROM sessions WHERE id = ?"); $sqldata = array ($PHP_AUTH_USER); if (!odbc_execute($stmt, &$sqldata) || !odbc_fetch_into($stmt, &$tmp)) {     // if the execute or fetch fails, initialize to empty array     $session_data = array(); } else {     // we should now have the serialized data in $tmp[0].     $session_data = unserialize($tmp[0]);     if (!is_array($session_data)) {         // something went wrong, initialize to empty array         $session_data = array();     } } ?>

See also serialize().