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serialize

(PHP 3 >= 3.0.5, PHP 4, PHP 5)

serialize -- Generates a storable representation of a value

Description

string serialize ( mixed value )

Generates a storable representation of a value

This is useful for storing or passing PHP values around without losing their type and structure.

To make the serialized string into a PHP value again, use unserialize().

Parameters

value

The value to be serialized. serialize() handles all types, except the resource-type. You can even serialize() arrays that contain references to itself. Circular references inside the array/object you are serialize()ing will also be stored. Any other reference will be lost.

When serializing objects, PHP will attempt to call the member function __sleep() prior to serialization. This is to allow the object to do any last minute clean-up, etc. prior to being serialized. Likewise, when the object is restored using unserialize() the __wakeup() member function is called.

Return Values

Returns a string containing a byte-stream representation of value that can be stored anywhere.

Examples

Example 1. serialize() example


<?php
// $session_data contains a multi-dimensional array with session
// information for the current user.  We use serialize() to store
// it in a database at the end of the request.

$conn = odbc_connect("webdb", "php", "chicken");
$stmt = odbc_prepare($conn,
      "UPDATE sessions SET data = ? WHERE id = ?");
$sqldata = array (serialize($session_data), $_SERVER['PHP_AUTH_USER']);
if (!odbc_execute($stmt, &$sqldata)) {
    $stmt = odbc_prepare($conn,
     "INSERT INTO sessions (id, data) VALUES(?, ?)");
    if (!odbc_execute($stmt, &$sqldata)) {
        /* Something went wrong.. */
    }
}
?>

ChangeLog

Version	Description
4.0.7	The object serialization process was fixed.
4.0.0	When serializing an object, methods are not lost anymore. Please see the Serializing Objects for more information.

Notes

Note: It is not possible to serialize PHP built-in objects.