passing registered objects to next page?

Anon

Hello

Estimating the probability of experiencing this problem in the beginning of PHP coding there might be a lot answers out there, please don't get angry because of the beginner level this question comes from [a DB search didn't get me any satisfying results]. Well, here we go.

PAGE 1:
session_start();
include("vehicle.inc");

$motorcycle = new Vehicle;
session_register("motorcycle");
<a href="page2.php">Link to page2</a>

PAGE 2:
session_start();
include("vehicle.inc");

$motorcycle->go(55);

VEHICLE.INC:
class Vehicle {

var $model;
var $miles_per_hour;

function go($speed) {
	$this->miles_per_hour = $speed;
	print "<BR>The $this->model is going $this->miles_per_hour m.p.h.<BR>";
}

}

When clicking from page 1 to page 2 an error message with this content appears:
###
Fatal error: The script tried to execute a method or access a property of an incomplete object. Please ensure that the class definition vehicle of the object you are trying to operate on was loaded before the session was started
###

And yes I tried some variants of including the vehicle before/after the registersess(), did that on page 1 and page 2.

Thanks in advance for help.

Anon

Your problems are a result of your methods. Use objects on a per-page basis. If you need to use a similar object, pass a string (or store it in the session) that will help you recreate the object on another page.

Using objects as session variables isn't a real good idea....just stick with scalar values as session values.

Anon

I don't see why objects aren't fine as session variables. Why do you think so?

Anon

The latest version of PHP has some object serialization problems (object serialization/de-serialization is needed internally by PHP when using objects as session variables).

If you either use a snapshot version of PHP or use a patched PHP; then it should work well again. For a source patch:
http://rpms.arvin.dk/php/source/patches/php-var.c.patch

If you use Red Hat Linux, then here is a binary version of the patched PHP:
http://rpms.arvin.dk/php/

Anon

Since sessions only pass properties and not methods you need to create a new object of the same class and name as the registered object before calling session_start().

PAGE 2:
include("vehicle.inc");
$motorcycle=new Vehicle;
session_start();
$motorcycle->go(55);

In this case session_start() will populate the $motorcycle object with the properties from the $motorcycle object on the first page.

Anon

Thanks alot, this seems to work. If I encounter any further problems with this method I'll post it here.

regards,
Pantheon

Anon

My host's ISP is running 4.0.3pl1 , and it all works perfectly. Thank you anyway.