Session input field interaction problems.

fredfish666

Hi all,
I am relatively new to all this so please be gentle!

At present I have self referencing script which uses variables set by input fields to search on a database. All was going fine until I decided I wanted to remember the last values the user set in the fields. In JavaScript I used to use cookies.

Sessions appear to do what I want so I am registering the name of a variable but the problem is when I change the field and resubmit the field goes back to the saved value!

This is the gist..
session_start();
session_register("fredx");
echo" <form action=$PHP_SELF method=post>";
echo" <input type='text' name='fredx' >
echo" <input type='submit'>";
echo"</form>";

How do I specifically set $_SESSION[fredx] when the field is changed? I would have thought it was an automatic thing!

cheers

packland

i'm fairly new as well but i think that basically you have a dual use variable (overloaded) and you should separate this

Registered session variable: fredx
member of $HTTP_POST_VARS variable: fredx

something like:

session_start();
session_register("fredx");
$fredx = maryx
echo" <form action=$PHP_SELF method=post>";
echo" <input type='text' name='maryx' >
echo" <input type='submit'>";
echo"</form>";

packland

I'm not sure i've answered your question.

no the text field and the session variable are not related.

You can use javascript to detect events and set values for session variables on events related to forms. You can also change the information you submit and do all sorts of stuff with javascript.

In your example you need to use another variable. Exactly how you use it depends on what you want to do.

anther eaxample might be:

session_start();
if (!fredx) {
   session_register("fredx");
}
//old value is still fredx
$oldvalue=$fredx
//set session variable ($fredx) to new value
$fredx = maryx
echo" <form action=$PHP_SELF method=post>";
echo" <input type='text' name='maryx' >
echo" <input type='submit'>";
echo"</form>";

packland

phew ...
sorry that had too many typos try this

<?
session_start();
if (!fredx) {
   session_register("fredx");
}

//old value is still fredx
$oldvalue=$fredx;

//set session variable ($fredx) to new value
$fredx = "maryx";
?>
<form action="<? echo $PHP_SELF; ?>" method=post>"
<input type='text' name='maryx' value="<? echo "fredx"; ?>">
<input type='submit'>
</form>

packland

sorry - very tired ... not trying to get more posts this has 2 more typos removed

<?
session_start();
if (!$fredx) {
   session_register("fredx");
}

//old value is still fredx
$oldvalue=$fredx;

//set session variable ($fredx) to new value
$fredx = $maryx;
?>
<form action="<? echo $PHP_SELF; ?>" method=post>"
<input type='text' name='maryx' value="<? echo "fredx"; ?>">
<input type='submit'>
</form>

i'll let someone else have a go now!!!

bye

fredfish666

Cool, thanks so much for the help Packland.

That has got me up and running again. Honestly this session business was beginning to do my head in! The trick was as you said to use 2 variables.

One extra bit was the stickyness so $fredx is only updated it there is a value in $maryx.

Anyway one more question - any idea how would I make it remember the value after I restart the browser?

Thanks again 🙂

Cheers

(I have included the code I have used just for future ref)

<?
session_start();
if (!$SESSION[fredx]) {
session_register("fredx");
}
echo "Current saved=" . $fredx . "<br>";

if ($maryx) $fredx=$maryx;

echo" <form action=$PHP_SELF method=post>";
echo" <input type='text' name='maryx' value='" . $fredx ."'>";

echo" <input type='submit'>";
echo"</form>";

echo "<br>To save=" . $fredx;
echo "<br>New=" . $maryx;

packland

You have to use cookies. i've been trying to not use cookies in my projects so i havn't done much here yet.

note there is essentially three methods for saving state:

cookies (only alternative to session variables) - can last for v. long times
session variables with cookies on => session cookies - the clients browser automatically sets a cookie to store the session id. This cookie lasts as long as the session
can set session up explicitely:
session_set_cookie_params(3600,"/",getenv('HTTP_X_HOST'));
session variables with cookes off - only works if you send the session id with each request
$form_block = "<form action=\"".$PHP_SELF."?".SID."\" method=\"post\">\n";

suntra

I don't know what version of PHP you're using, but you should always use $_SESSION["variable_name"] and not $variable_name. Security reason...

How to register a session variable with $_SESSION ? Very simple !

$_SESSION["variable_name"] = "value";

You must remember something : NEVER USE session_register() WHEN YOU USE $_SESSION or $HTTP_SESSION_VARS, NEVER ! I had done that before, and when I turned register_globals to Off (what all of us should do), my session variables still registered, but no value !!!

So, if possible :
1. only use $SESSION (or $HTTP_SESSION_VARS), never the variable (single)... $SESSION["variable"], not $variable.
2. don't use session_register() with $_SESSION or $HTTP_SESSION_VARS.
3. Turn register_globals to Off.

fredfish666

I have had session cookies working so now the session is remembered and recalled.

I will try to use $_SESSION from now on. I take it that local variables that are not to be remembered can still be used as $variable_name..

Am I right in saying that register_globals is a php.ini option so I can't modify it without server access ?

cheers

Alan

packland

Yes register globals is a php.ini option so you can't access it without admin privileges. This seems to be a fairly common implementation for web hosting etc. - must get around to reading all the pitfalls.

Thanks Suntra - something i was unsure about also. fredfish666, I think because the other (local) variables you use exist temporarily on the server (only when a user accesses a specific page) there is much less complication.