Initialze a Session

[doubledee]

I am debugging my Log-In module and would like to erase data that was stored in my $_SESSION variable from my prior debugging session.

 

(It will just be easier for me to follow what is going on if all variables in my SESSION are null.)

 

How do I do that?

 

Where do I do that?

 

Do I destroy the SESSION and then start it?

 

Or do I start the SESSION and then destroy it? 

 

 

 

Debbie

 

[gizmola]

I'd suggest a simple function:

 

function cleanSession() {
  foreach($_SESSION as $sessvar) {
    unset($sessvar);
  }
}

 

Add it where you want to insure that there are no set session variables.

[doubledee]

I'd suggest a simple function:

 

function cleanSession() {
  foreach($_SESSION as $sessvar) {
    unset($sessvar);
  }
}

 

Add it where you want to insure that there are no set session variables.

 

 

But I call that function after I start the session in my header?

 

 

Debbie

 

[gizmola]

Yes.

[doubledee]

Yes.

 

Why not just destroy the session?

 

 

Debbie

[gizmola]

Because then you would have to reinitialize the session.  You stated you wanted to have something you could drop in for testing purposes that doesn't do black magic with the session handler.  If you really want to use session_destroy then you'd have to have:

 

session_start();

session_destroy();

session_start();

[doubledee]

Because then you would have to reinitialize the session.  You stated you wanted to have something you could drop in for testing purposes that doesn't do black magic with the session handler.  If you really want to use session_destroy then you'd have to have:

 

session_start();

session_destroy();

session_start();

 

Oh, okay.

 

 

Debbie

 

[codefossa]

Well, it wouldn't be that bad lookin'.

 

$session_id = session_id();

if (empty($session_id))
    session_start();

if (isset($_GET['logout']))
{
    session_destroy();
    session_start();
}

 

The session_start func should be there no matter what.  The logout may have more to it as well (assuming that's why you're destroying it), but same thing pretty much no matter what.

[doubledee]

I'd suggest a simple function:

 

function cleanSession() {
  foreach($_SESSION as $sessvar) {
    unset($sessvar);
  }
}

 

By the way, I added your code in like...

 

<?php
// Initialize a session.
session_start();

foreach($_SESSION as $sessvar) {
	unset($sessvar);
}

 

But when I step through NetBeans it isn't re-setting my SESSION variables?!

 

 

Debbie

 

 

[darkfreaks]

i am going to download netbeans on Ubuntu and see why 

[requinix]

I think gizmola was aiming more for

foreach(array_keys($_SESSION) as $sessvar) {
  unset($_SESSION[$sessvar]);
}

Right now it'll just unset $sessvar and that won't affect what's in $_SESSION.

[gizmola]

Yes my bad -- thank requinix.

 

 

[doubledee]

I think gizmola was aiming more for

foreach(array_keys($_SESSION) as $sessvar) {
  unset($_SESSION[$sessvar]);
}

Right now it'll just unset $sessvar and that won't affect what's in $_SESSION.

 

I don't get it?!

 

I thought "un-setting" was like erasing each attribute?

 

So what should it be to erase each value?

 

 

Debbie

 

 

[requinix]

It should be what I posted.

 

unset() will destroy values in memory according to what variable you give it. If you

$a = 1;
$b = $a;
unset($b);

then you are destroying $b, and that has no bearing on what happens to $a. Similarly

foreach ($array as $value) {
    unset($value);
}

will destroy $value, and that has no bearing on what happens to $array. By using array keys like

foreach (array_keys($array) as $key) {
    unset($array[$key]);
}

then you are destroying $array[$key].

[doubledee]

It should be what I posted.

 

unset() will destroy values in memory according to what variable you give it. If you

$a = 1;
$b = $a;
unset($b);

then you are destroying $b, and that has no bearing on what happens to $a. Similarly

foreach ($array as $value) {
    unset($value);
}

will destroy $value, and that has no bearing on what happens to $array. By using array keys like

foreach (array_keys($array) as $key) {
    unset($array[$key]);
}

then you are destroying $array[$key].

 

But even if I use your original code and just "unset" the Session values, should I see the values go to '' or null in NetBeans as the code runs through the loop?

 

 

Debbie

 

 

[requinix]

I don't know what NetBeans will do. I would expect null because the variables/values no longer exist.

[gizmola]

Yeah not sure about netbeans debugger -- things should go null on an unset(), but even if they don't you could verify easily that they are gone using vardump.  This is the entire purpose of unset().