storing class instance into session

nizzy · 10-02-2008, 02:50 AM

Do you think SetObject() method will work?

PHP Code:


			
class Session

{

    ...........

    ...........



    public function SetObject($class_name)

    {

        if(!isset($_SESSION[$class_name]))

        {

            $num_args = func_num_args();

            $params = array();



            if($num_args == 1)

            {

                $obj_ins = new $class_name();

            }

            elseif($num_args > 1)

            {

                $get_args = func_get_args();

                $params = array_shift($get_args);



                $obj_ins = call_user_func_array($class_name, $params);

                //$obj_ins = call_user_func_array(array($this, 'parent::__construct'), $params); // not sure about this one

            }



            $_SESSION[$class_name] = serialize(new $obj_ins());

        }

    }



    public function GetObject($class_name)

    {

        if(isset($_SESSION[$class_name]))

        {

            $instance = unserialize($_SESSION[$class_name]);



            if($instance instanceof $class_name)

            {

                return $instance;

            }

        }

    }

}



$sess_handler =& new Session();



//storing class instance into session

$sess_handler->SetObject('FooBar', $arg_1, $arg_2, $arg_3....etc);



//getting class instance from session

$foo_bar = $sess_handler->GetObject('FooBar');



$foo_bar->print_hello(); // this is a method in FooBar class

Kalle · 10-02-2008, 03:49 AM

Its possible to serialize object instances and store them in session variables, you just have to remember to include the class declaring before the session_start() call, else deserialized instances will become an instance of __PHP_Incomplete_Class.

nizzy · 10-02-2008, 04:01 AM

Dear Kalle

Thanks for quick reply. Then my method will not work, because I am trying to store the FooBar class into $_SESSION var AFTER the session is created. I see this is the problem.

Now, how about this? is this the right way of applying the params to a CLASS (not a function)

$obj_ins = call_user_func_array($class_name, $params);

thank you

nizzy · 10-02-2008, 06:49 AM

YES! you can store object instance into session AFTER session initialization.

THE WHOLE trick resides in these lines (requires php v5.1.3):
$reflection_obj = new ReflectionClass($class_name);
$obj_ins = $reflection_obj->newInstanceArgs($get_args);

PHP Code:


			
<?php



class FooBar

{

    public $arg_1;

    public $arg_2;

    public $arg_3;



    public function __construct($arg_1, $arg_2, $arg_3)

    {

        $this->arg_1 = $arg_1;

        $this->arg_2 = $arg_2;

        $this->arg_3 = $arg_3;

    }



    public function hello()

    {

        return "hello from __CLASS__, arg_1: " . $this->arg_1 . ", arg_2: " . print_r($this->arg_2, true) . ", arg_3: " . $this->arg_3;

    }

}



class Session

{

    public function __construct()

    {

        session_start(); 

    }



    public function SetObject($class_name)

    {

        unset($_SESSION[$class_name]); 



        if(!isset($_SESSION[$class_name]))

        {

            $num_args = func_num_args();

            $params = array();



            if($num_args == 1)

            {

                $obj_ins = new $class_name();

            }

            elseif($num_args > 1)

            {

                $get_args = func_get_args();

                array_shift($get_args);



                $reflection_obj = new ReflectionClass($class_name); 

                $obj_ins = $reflection_obj->newInstanceArgs($get_args); 

            }



            $_SESSION[$class_name] = serialize($obj_ins);

        }

    }



    public function GetObject($class_name)

    {

        if(isset($_SESSION[$class_name]))

        {

            $instance = unserialize($_SESSION[$class_name]);



            if($instance instanceof $class_name)

            {

                return $instance;

            }

        }

    }

}



$sess_handler =& new Session();



//storing class instance into session

$sess_handler->SetObject('FooBar', 'first_str', array('hey', 'budy'), true);



//getting class instance from session

$foo_bar = $sess_handler->GetObject('FooBar');



//var_dump($foo_bar);



echo $foo_bar->hello(); // this is a method in FooBar class 



?>