sessions, need explanation

[Incubator]

I read the info of session managment on php.net, however when I tried to implement it, it didnt work out so well.

here is a small piece of code that shows what I am currently doing:

<?php
        session_start();
          // if the user submitted the form, retrieve data, process and check with database ...
         // put  a number into the variable $number, we want to remember this one
         if(!isset($_SESSION['anumber']))
               $_SESSION['number']  = $number;

     header("Location: nextpage.php?".strip_tags(SID));
     exit;
?>

in nextpage.php : 

<?php
         session_start();
          if(isset$_SESSION['number']))
              $number = $_SESSION['number'];

     // display the records that are from user with htis number

?>

whzt I get in my adress bar is this:

nextpage.php?
and sometimes the three characters SID are pasted after it.
but I get no session id.

Note that I cannot pass the session id with cookies, since the users are not comfortable with using a computer at all, most likely having their browser left at default settings, blocking some cookies.

Now, I dont know if this is the right way to use sessions, but still, could someone shed some light into this?

[yelvington]

Why are you referring to two different session variables -- $SESSION['anumber'] and $SESSION['number']?

Did you test the code you posted? The following line:

if(isset$SESSION['number']))
should read
if(isset($SESSION['number']))

Do you have cookies disabled in the browser you are using to test this? If you do not, on all but the first access, SID should evaluate to a null string, and the URL will end in a question mark with no arguments. This is explained in the sessions documentation.

I cleaned up your errors, added $number=4 in the first file, and tested the result. It works just the way it should.

[Incubator]

those are just some typing mistakes, I didnt copy/paste it.

I tested it with Mozilla 1.5, all cookies allowed

the session variable is correctly stored, only the SID wont come through, so the second page doesnt know about it.

[yelvington]

Again,

Session management uses cookies by default. If the session module sees a session cookie, SID will be NULL.

If you hit the same page with cookies disabled, SID will contain a key=value pair for the session ID.

[Incubator]

I see.
then how can I make sure that both those with cookies and those without can log in?

[yelvington]

To support ONLY users who allow cookies, use sessions without worrying about the SID trick.

To support users who disable cookies AND users who allow cookies, append the SID to the URL as explained in the manual.

COOKIE USERS WILL NOT SEE ANYTHING THERE. If you test your code using a browser that sends cookies, YOU will not see the session ID in the URL.

This is not a problem.

This is how it is supposed to work.

Cookie users don't need to see the SID. They have cookies.

Only users who disable cookies need to see the SID, therefore PHP populates the SID only if cookies are not detected.

If you are doing this, and the $_SESSION array is not being populated on subsequent pages, then you need to look elsewhere in your code for an error.

[Incubator]

well, it seems to remember the sesion vars right, I just dont understand why it wont work anymore, before I added sessions support, I could make it work :s

here is a long part of code, just ignore all the dutch in it
I left out a lot of html, so dont look at that either, the php code is all that matters anywhay.

Page 1 - log in

<?php
                session_start();
	$message="";  //error message
	if ($_POST['login']) { // if the user submitted


	$db = mysql_connect("localhost",$dbuser,$dbpassword) || die("Unable to connect to database".mysql_error());
	mysql_select_db("carege_acrogym") || die("Unable to open Database".mysql_error());
	$username = $_POST['user'];
	$password = $_POST['pass'];
	$query = "select Email, ClubID from tblClubgegevens where lower(Clubnaam) = '".strtolower($username)."'";
	$result = mysql_query($query);
	$row = mysql_fetch_row($result);
	$num_rows = mysql_affected_rows();

	if ($num_rows ==1) {

		if (trim($password) == $row[0]) {
			$clubid = $row[1];

                                                             $_SESSION['clubid'] = $clubid;

                            $location = "acrogeg2.php?".strip_tags(SID);
			header("Location: $location"); /* Redirect browser */
			exit; //make sure we don't execute the rest of the code when redirecting
		} else {
			$message = "Uw passwoord is fout! Vul uw emailadres van de club";
			$message .= " als wachtwoord.";
		}
	} else {
		$message = "Uw login en passwoord is fout! Vul uw Clubnaam in als Gebruikersnaam en het emailadres van de club";
		$message .= " als wachtwoord. Indien U de juiste login gegevens ingevuld hebt, gelieve U dan in te schrijven.";
	}
}
?>
<html>
<body>
<table border="0" width="100%" height="100%">
<tr><td width="100%" align="center">

<table border="0" cellpadding="0" cellspacing="0" width="500">


   <!-- invoer -->
   <form name="input" method="post" action="<?php echo $_SERVER['PHP_SELF']."?".strip_tags(SID); ?>">
     <table border="0"><tr><td colspan="3"><font color="red"><?php echo $message; ?></font> </td></tr>
       <tr>
         <td width="35%" align="right">Gebruikernaam<br><br>E-mail</td>
         <td width="10%">&nbsp;</td>
         <td width="55%">
         <input type="text" name="user" size="28"><br><br>
         <input type="text" name="pass" size="28">
		 </td>
       </tr>
     </table><br>
     <input type="submit" name="login" value="verder gaan"><br>    
    </form><br>

    </td>
   <td width="12"><img border="0"src="border_e.gif" width="12" height="100%"></td>
 </tr>
 <tr heigth="1">
   <td colspan="3" bgcolor="#000000"></td>
 </tr>
</table> 
</td>
  </tr>
</table>


</td></tr></table>
</body></html>

page 2, this should display hte groups that belong to that specific club

<?php
          session_start();
	$groepid = 0;
	$message = "";
if (isset($_SESSION['clubid']))
	$clubid = $_SESSION['clubid'];

$db = mysql_connect("localhost", $dbuser, $dbpassword);
mysql_select_db("carege_acrogym");
if (isset($gid)) {
	if ($del == true) {
		mysql_query("delete from tblGymnasten where GroepID = $gid");
		mysql_query("delete from tblGroepen where GroepID = $gid");
	}
}
if ($_POST['toevoegen']) {


	$query = "insert into tblGroepen (ClubID, categorie) values('$clubid','acro')";
           echo $query;
	mysql_query($query);
	// give me the groep I just made
	$query = "select max(GroepID) from tblGroepen where ClubID  = ".$clubid."and categorie = 'acro'";
	$result = mysql_query($query);
	$row = mysql_fetch_row($result);
		// add gymnast 1
		$naam = $_POST['gymnast1'];
		$geslacht = $_POST['geslacht1'];
		$dag = $_POST['dag1'];
		$maand = $_POST['maand1'];
		$jaar = $_POST['jaar1'];

		if (trim($naam) == "" || trim($geslacht) == "" || trim($dag) == "" || trim($maand) == "" || trim($jaar) == "") {
			$message = "Alle velden moeten ingevuld zijn";
		} else {
			$datum = $jaar.'-'.$maand.'-'.$dag;
			$groepid = $row[0];
			$query = "insert into tblGymnasten(GroepID, Naam, Geslacht, GebDatum) values('$groepid','$naam','$geslacht','$datum')";
			mysql_query($query);
		}

		//  add gymnast 2
		$naam = $_POST['gymnast2'];
		$geslacht = $_POST['geslacht2'];
		$dag = $_POST['dag2'];
		$maand = $_POST['maand2'];
		$jaar = $_POST['jaar2'];

		if (trim($naam) == "" || trim($geslacht) == "" || trim($dag) == "" || trim($maand) == "" || trim($jaar) == "") {
			$message = "Alle velden moeten ingevuld zijn";
		} else {
			$datum = $jaar.'-'.$maand.'-'.$dag;
			$groepid = $row[0];
			$query = "insert into tblGymnasten(GroepID, Naam, Geslacht, GebDatum) values('$groepid','$naam','$geslacht','$datum')";
			mysql_query($query);
		}


}
?>
<html>
<body>
<table border="0" width="100%" height="100%">
<tr><td width="100%" align="center">

<table border="0" cellpadding="0" cellspacing="0" width="500">
  <tr>
    <td>
     <table border="0" cellpadding="0" cellspacing="0" width="100%" height="100%">
      <tr height="12">
  	   <td colspan="3">
  	     <table border="0" cellpadding="0" cellspacing="0" width="100%"><tr>
           <td width="12"><img border="0" src="border_nw.gif" width="12" height="12"></td>
    	   <td width="88"><a href="clubwijz.php?<?php echo strip_tags(SID) ?>"><img border="0" src="d_club.gif" height="12" width="88"></a></td>
    	   <td width="42"><a href="acrogeg2.php?<?php echo strip_tags(SID) ?>"><img border="0" src="a_acro.gif" height="12" width="42"></a></td>
    	   <td width="59"><a href="tumbgeg1.php?<?php echo strip_tags(SID) ?>"><img border="0" src="d_tumb.gif" height="12" width="59"></a></td>
    	   <td width="100%"><img border="0" src="border_n.gif" width="100%" height="12"></td>

   <form name="acro" method="post" action="<?php echo $_SERVER['PHP_SELF']."?".strip_tags(SID); ?>">
   <table border="0" cellpadding="0" cellspacing="0" width="100%">
 <tr>
       <td valign="top" rowspan="3">
       <a href="acrogeg2.php?<?php echo strip_tags(SID); ?>"><img border="0" src="btn.gif" width="9" height="11"> Duo</a><br>
       <br>
       <a href="acrogeg3.php?<?php echo strip_tags(SID); ?>"><img border="0" src="btn.gif" width="9" height="11"> Trio</a></td>

   </table>
   <input type="submit" value="Voeg toe" name="toevoegen"><p></p>
   </form>
 <table border="1" cellpadding="0" cellspacing="0" style="border-collapse: collapse" bordercolor="#111111" width="100%" id="AutoNumber1">
     <?php
 	$db = mysql_connect("localhost", $dbuser, $dbpassword);
	mysql_select_db("carege_acrogym");
 	$result = 0;
 	$query = "select gr.GroepID, Naam, Geslacht, GebDatum ";
	$query .= "from tblGymnasten gy, tblGroepen gr ";
	$query .= "where gy.GroepID = gr.GroepID  and ClubID = ".$clubid." and categorie = 'acro'";
	$result = mysql_query($query);
	$temp = 0;

if (mysql_affected_rows() >0) {
	while ($row = mysql_fetch_array($result, MYSQL_NUM)) {
		if ($temp == 2) $temp = 0;
		echo "<tr>\n<td>$row[0]</td><td width=\"25%\">$row[1]</td>\n";
		echo "<td width=\"25%\">".(($row[2] == 'm')?"Man":"Vrouw")."</td>\n";
		echo "<td width=\"25%\">$row[3]</td>";
		if ($temp == 1)
			echo "<td width=\"25%\"><a alt=\"Verwijder deze groep\" border=\"0\" href=\"acrogeg2.php?".strip_tags(SID)."&amp;amp;gid=$row[0]&amp;amp;del=true\"><img border=\"0\" src=\"btn.gif\">Verwijder</a></td></tr>\n";
		else
			echo "<td width=\"25%\">&nbsp;</td></tr>";
		$temp++;
	}
} else {
	echo "Er zijn geen groepen ingeschreven";
}
 ?>
   </table>
   <br><br>
   </td>
   <td width="12"><img border="0" src="border_e.gif" width="12" height="100%"></td>
 </tr>
 <tr heigth="1">
   <td colspan="3" bgcolor="#000000"></td>
 </tr>
</table>  

</td></tr></table>
</body></html>