[Resolved] session unset and looping

[lobster]

OK. I am in session hell. Hope someone can help me.

update.php is a form
submits to dbupdate.php

validate - if there is an error write posted variables to a session to populate the form

back to update.php - the sessions populate the fields but when I make changes and submit again without errors, it will not see the changes and does not update the database ... it retains the session values instead.

Also, if I go to update another item... it still shows some of the session data from the last one.

I have tried ot loop through and unset session values with no success. I have treid putting $_REQUEST before variables and am running into issues.

Here is the top of update.php (I have to retain the login session var)

   $login = $_SESSION['login'];

 if(isset($_REQUEST['errmsg'])){
  $errmsg = $_REQUEST['errmsg'];
   } else {
      $errmsg = "";
   }

   if(isset($_REQUEST['submit'])){
      $submit = $_REQUEST['submit'];
   } else {
      $submit = "";
   }

   if(isset($_REQUEST['process'])){
      $process = $_REQUEST['process'];
   } else {
      $process = "";
   }

  // if this is an update page and not a new listing
  // supply the action for updating a vessel
  // if there is no error then they just got here and we need to load the database data
  // else they have entered data and got an error... the dbupdate pages loads the variables back to this page.
   if ($process == "update"){
    $actionURL = "dbupdate.php";
   		if($errmsg == ""){
         include("loaddata.php"); // loads from db
   		}
		else if($errmsg !=""){
		 include("header_session.php"); // load session data
		}
   } else {
    $actionURL = "dbinsert.php";
   	if($errmsg == ""){
         include("list_init.php");
   	}
   }

And here is a portion of the dbupdate page:

 /*#########
    * Start of the main function.
   ########### */
   session_start();
   include("db_connect.php");
   //Updates - have to update pictures first since th e sessions will not save them
   	 include_once("update-pictures.php");   

   $errmsg = "";
   include('validate.php'); // all have $_request 
   if($errmsg != ""){
   	$header_variables = "";
   	include('header_variables.php');
   	//Redirect the error message back to the add boat page.
   	header("location:update.php?process=update&errmsg=$errmsg");
   	exit;
   }  

I can post more but I dont know where to start.

[bpat1434]

Well you say you have a problem with the new values being read AFTER you try and update again. Where is that code? You never unset() the session, nor do you clear the session variables. That's the code that would help you even more.

~Brett

[lobster]

i think that is where I get confused... I tried putting the unset code in there but I think I am unsure exactly where that should go and the places I did try it threw errors..

I tried doing this:

foreach ($_SESSION as $Key => $Value)  { 
   if($Key != 'login') unset ($_SESSION[$Key]); 
} 

Can I loop and do a conditional statement like this?

[bpat1434]

I stand corrected, and yield to the better answer(s) below.

~Brett

[lobster]

I had to use sessions because I could not put the variables back through the URL since there are so many and they are so big. So when the user gets a validation error... they would lose all of the fields entered before.

I am new to sessions and thought this was the only way to fix the issue. But in fixing one thing... it has screwed up a lot more since I have not figured out how to destory the session while keeping the login session.

I tried your code but I get the error:
cannot use [] for reading

where we are calling $_SESSION[]

Should I remove the [] ?

[wempy]

If you need to keep part of the session data, but not others, you colud put all of the form data into an array, and store that in the session, then when you need to erase the form data, but not the login details, just erase the array.

[bradgrafelman]

What I believe wempy is talking about is an approach I was thinking of myself: Multiple arrays.

The structure of $_SESSION[] would look like this:

Array (
'login' => 1,

'form' => array(
                 'element_1' => 'value_1',
                 'element_2' => 'value_2',
                 'etc' => 'and so on'
                )
)

So that you would check for login by using $_SESSION['login'], and then you could load all the form variables like so:

foreach($_SESSION['form'] as $key => $val) ${"form_".$key} = $val;

would populate the variable:

$form_element_1 = 'value_1';
$form_element_2 = 'value_2';
$form_etc = 'and so on';

Now you can easily search/replace form elements, or destroy the form data by using:

unset($_SESSION['form']);

Hope this is what you meant.

EDIT: An error in my foreach() statement was fixed.

[lobster]

OK. I kind of get it...

How would I put the array part you did first into the session?

I am missing that part.

So basically if validate throws an error..
I will write the form values to the session in an array.

[bradgrafelman]

Woops... heh.. forgot to provide that, didn't I?

Something like this:

$_SESSOIN['form'] = array();
foreach($_POST as $key => $val) $_SESSION['form'][$key] = $val;

Simple!

[lobster]

ah... cool!

If I dont want to rename the key would I do the following

foreach($_SESSION['form'] as $key => $val) $key = $val;

or do I need the { } around $key?

[bradgrafelman]

I added "form_" to the variable for security purposes; otherwise, without it, a user could submit a FORM element and override one of your variables in your scripts (security vunerability).

If you would rather just use the element's name as the variable name, then yes, you can use the code you have posted.

(The { and } were just there so that PHP would process the stuff as code instead of literally assigning a variable name)

[lobster]

Ok... I see the purpose. One problem I am havgin is that I am getting a T_VARIABLE error where I am putting someof the code:

   		if($errmsg == ""){
         include("inc/z_loaddata.php");
   		}
		else if($errmsg !=""){
	foreach($_SESSION['form'] as $key => $val){_$key_=_$val;}
		}

[bradgrafelman]

What are you trying to make the variable name be?

Any 'string' that you're attaching to the variable name must be concatenated as a string (using quotes and periods).

Give me an example. Let's say I submit a form with an element name of "foo". What should your PHP variable look like?

[lobster]

oh ok.. so I submit foo

there is a validation error and I put all of the $_POST vars into the array as you described above.

I need to load the form again with this array data and not the db data

so in the code I put

 
foreach($_POST as $key => $val) $_SESSION['form'][$key] = $val;

and then load the form and get all the posted data with:

foreach($_SESSION['form'] as $key => $val){ $key = $val;

[bradgrafelman]

foreach($_SESSION['form'] as $key => $val){ $key = $val;

I'm assuming you have a statement enclosed in { }, otherwise you've gotta extra '{'.

Otherwise, the code looks fine and should do exactly what you want it to.

[lobster]

Yeah I have a closer... dont know why I am getting the T_variable error on that line then...works when I comment it out... will work with it a bit more.

[bradgrafelman]

If you can't get it, re-post the code (include areas around that line) so I can get a broader view of it.

[lobster]

Yeah... Cannot get it to work

get an unexpected t-variable error with this code which writes the session:

   session_start();
   include("db_connect.php");
   //Updates
   include_once("../update-pictures.php");
   //Insert Logged in User

   $errmsg = "";
   include('z_addboat_validate.php');
   if($errmsg != ""){
  	$_SESSION['form']_=_array(); 
	foreach($_POST as $key => $val){ $_SESSION['form'][$key] = $val;}
   	//Redirect the error message back to the update boat page.
   	header("location:../admin.php?process=update&errmsg=$errmsg");
   	exit;
   }

[bpat1434]

What is this line trying to do?

 $_SESSION['form']_=_array();  

If you're just defaulting it to empty, it should be:
$_SESSION['form'] = array();

~Brett

[lobster]

ok.. took that out and dont get that error but I do get the same error on the other page that tryies to call the array:

      // if this is an update page and not a new listing
	  // supply the action for updating a vessel
	  // if there is no error then they just got here and we need to load the database data
	  // else they have entered data and got an error... the dbupdate pages loads the variables back to this page.
   if ($process == "update"){
		$actionURL = "inc/z_addboat_dbupdate.php";
			if($errmsg == "")
			{
			 include("inc/z_loaddata.php");
			}
			else if($errmsg !="")
			{
				foreach($_SESSION['form'] as $key => $val) 
				{
					$key =_$val;
				}
			}
	} else {
		$actionURL = "inc/z_addboat_dbinsert.php";
		if($errmsg == "")
		{
			 include("inc/list_init.php");
		}
   }