isset() Problem

alsaffar

Hi there,

I have a page that have the following code:

<?
if (!isset($SID))
{
$SID = mt_rand();
echo $SID;
}
else
{
echo "SID already set";
}
?>

The problem is everytime I hit refresh button (F5) the variable is re-created! I want only to create that variable only if its the first time the user enter that page.

Please I appreciate your help.

cahva

Sessions would be good in this situation:

<? 
session_start();
if (!isset($_SESSION['SID'])) 
{ 
$_SESSION['SID'] = mt_rand(); 
echo $_SESSION['SID']; 
} 
else 
{ 
echo "SID already set"; 
} 
?>

alsaffar

Forget that SID is SessionID, assume it any varibale (lets say ID) and I want this variable (ID) to be careated once, and when the user hit the refresh button (F5) it will not be re-created.

So the code will be:

<?
if (!isset($ID))
{
$ID = mt_rand();
echo $ID;
}
else
{
echo "ID already set";
}
?>

One more thing I dont want to use session_start() becuse this command requires a cookie, and maybe the user disabled the cookies on his/her PC.

Please I apreciate you help.

JMM

Unless you're using sessions, each request -- you make a request when you click Refresh -- is completely separate and in that context there's no way your variable could already be defined. For each new request, there are some predefined variables provided by PHP, but your variables are defined as they're encountered in the script.

Using a session allows you to tie those separate requests together so that you can have variables defined for multiple requests. If you're worried about cookies there are several things you can consider: you can test the user's browser to see if it accepts cookies, or you can pass the session ID in the query string if you want, though cookies are preferable.

alsaffar

I can't remember which PHP's version that my webHost is using, but what I can remember very good that the PHP's version that my webHost is using is if the cookie is disabled the variable will not be inserted in the URL automatically! from this point I dont want to use sessions.

So, is there is any way to stop re-creating (ID) variable everytime the user hit the refresh button?

I know that in PHP you can play around anything and implement your crazy idea🙂

Anyway, Im intersted in how I can test the browser if its accepting cookies, but if its not accepting what shall I do with sessions if my PHP version not accepting to insert the session variable in the URL?