[RESOLVED] $_SESSION and simple_xml

deezerd

I stored some simple_xml data into sessions variables

Example

$_SESSION['resultat'] = $parsed->toto;

After that, I get the following error message

Warning: session_start() [function.session-start]: Node no longer exists in C:\Program Files\Wamp\www\etc... on line 2

And I finally solved my problem doing this:

$_SESSION['resultat'] = (string) $parsed->toto;

But I still have 2 questions:
1. Why is there an issue mixing $_SESSION and simple_xml in my code?

What is the use of the (string) before my variable? I mean, why does it solve the problem?[/B]

many thanks

mikell

Storing an object in a session variable is different than storing a string.
A string is just a series of characters, so storing a string and reading it back
is really "easy". Preserving an object between requests is more complicated.

For example:
"If you do turn on session.auto_start then you cannot put objects into your sessions since the class definition has to be loaded before starting the session in order to recreate the objects in your session.." - http://us3.php.net/session
*which means include the object's class definition before calling session_start().

"Some types of data can not be serialized thus stored in sessions. It includes resource variables or objects with circular references (i.e. objects which passes a reference to itself to another object)." - http://us3.php.net/session

Not sure about you're particular case, but hope that helps.

deezerd

thanks Mikell, you made it very clear for my first question 🙂

I guess then putting (string) before the variable just convert it into a string (I didn't know we could do it that way)

mikell

Exactly. Use (string) when you want some variable to be evaluated as a string in some expression. Just to be clear: (string), by itself, doesn't actually change the type of the variable it acts on.