I'm trying to do a simple test php script for sessions. Basically it increments a counter (stored in $_SESSION) every time you refresh that page. That works, but I'm trying to have a link to destroy the session which reloads the page with the ?destroy=1 parameter. I've tried a couple of if statements to see if that parameter is set and if so to destroy the session but it doesn't seem to work.
I've even put an if statement in the main body to pop-up a message if the parameter is set - but it doesn't seem to be picked up.
I know I'm doing something silly (I'm a PHP newbie) but I can't seem to find what it is...
See code here:
<?php
if ($_POST['destroy']) {
session_destroy();
} else {
session_start();
}
?>
<html>
<head>
<title>Session test</title>
</head>
<body>
<?php
if (isset($_POST['destroy'])) {
echo "Destroy set";
}
$_SESSION['counter']++;
echo "You have visited this page " . $_SESSION['counter'] . " times" . "<BR>";
echo "I am tracking you using the session id " . session_id() . "<BR>";
echo "Click here to destroy the session.";
?>
I think you put
$_POST['destroy']
Instead of
$_GET['destroy']
You need to use a form if you'd like to use a $_POST variable. $_GET variables are stored in the URL.
By the way you can use
$_REQUEST['destroy']
which would work regardless if the data is passed in a POST or a GET request.
In the PHP Manual it has code snippet for destroying a session.
session_start();
$_SESSION = array();
if (isset($_COOKIE[session_name()])) {
setcookie(session_name(), '', time()-42000, '/');
}
session_destroy();
Yeah, you're going to want to do
if( $_GET['destroy'] == 1 )
or
if( isset($_GET['destroy']) )
I know I'm doing something silly (I'm a php newbie) but I can't seem to find what it is...
that is how you are going to learn a lot ;) enjoy it ...
Related
Hey guys I'm trying to pass a php variable to another page. I tried it with sessions but no result.
newspaper.php
$newspaper= $newspaper['newspath'];
print_r($newspaper);
this outputs:
path/to/the/newspaper.
Now I want to use the variable in the second page.
newspaperviewer.php
echo $newspaper;
$SESSION = $newspaper;
I tried the first one but no result. The second one seems to be faulty.
Hope you guys can help me out.
Session is what you are looking for. A session variable can store a value and use this value on all pages of your project.
First thing to do is to start session on each file on your project. You can do this like this example
<?php
session_start(); //declare you are starting a session
$_SESSION['newspaper'] = "New York Times"; //Assign a value to the newspaper session
?>
On the other file you can use the value of the session by trying something like this
<?php
session_start(); //always start session don't forget!!
echo $_SESSION['newspaper'];
// This will echo New York Times
?>
Store the variable after starting session on page A, like so:
// FIRST PAGE (foo.php)
session_start();
$_SESSION['name'] = 'Jack';
Now, on the second page (or any page that you want to have access to $_SESSION, simply do the same but pull the variable.
// SECOND PAGE (bar.php)
session_start();
$name = $_SESSION['name'];
$_SESSION['name'] = null; // Or use session_unset() to delete all SESSION vars.
And that's how you pass variables using $_SESSION.
Please use this code to set session
<?php
// Start the session
session_start();
?>
<!DOCTYPE html>
<html>
<body>
<?php
// Set session variables
$_SESSION["favcolor"] = "green";
$_SESSION["favanimal"] = "cat";
echo "Session variables are set.";
?>
</body>
</html>
You can write like this
newspaper.php
session_start();
$newspaper= $newspaper['newspath'];
$_SESSION['newspaper'] = $newspaper;
Now you can use this session variable in
newspaperviewer.php
session_start();
$newspaper = $_SESSION['newspaper'];
echo $newspaper;
session_unset(); // remove all session variables
First
newspaper.php
$newspaper= $newspaper['newspath'];
//print_r($newspaper);
session_start(); //it starts your session here
$_SESSION['newspaper']=$newspaper; //it sets a session variable named as newspaper
Second
$newspaper= isset($_SESSION['newspaper'])?$_SESSION['newspaper']:''; //checks and sets value
echo $newspaper; //outputs value
For more see session_start
http://php.net/manual/en/session.examples.basic.php
First you will need to start the session by using session_start() at the top of your page. Second, a session variable is written like this: $_SESSION['foo'].
I suggest you read these pages to get a better understanding of what's going on.
http://php.net/manual/en/reserved.variables.session.php
http://www.w3schools.com/php/php_sessions.asp
My php website flows like this:
Page1.php has an html form which POSTs to Page2.php
Page2.php stores all the POST data into SESSION variables and has a button leading to Page3.php
Page3.php has another form which POSTs its data to Page4.php
Page4.php then stores all its POST data into SESSION variables
My problem is that it may be nessicary for a user to click the back button on Page4.php to go back to Page3.php and change some input. AS im sure your all aware when they get back to Page3.php the form will be blank as the entire page is re-rendered in its default state.
To get around this and re-display the user's previous input im doing this:
<input value="<?php echo $_POST["guest1Ticket"];?> " type="text" name="guest1Ticket" id="guest1Ticket" onblur="isTicketNumber(this)" size ="22"/>
This being the important part - <?php echo $_POST["guest1Ticket"];?>
This works but creates another problem for me. If the user goes back to Page1.php (before colsing their browser) and starts the process over again when they get to Page3.php the data from their last run through will be loaded into the form.
What I figure I need to do is clear all of the sdession variables when the user visists Page1.php. I tried to to that like this:
<?php
session_start();
session_unset();
session_destroy();
?>
(The above is at the very top of my file with no whitespace before the first character.)
No Warnings are generated when Page1.php loads but the session variables are not getting unset. When I get to Page3.php the data from the last run is still being entered into the form.
How can I clear my session data correctly?
BTW I only need this to work in Chrome and thats where im testing.
Only use session_unset() for older deprecated code that does not use $_SESSION.
see session_destroy manual
example you can try and see how it works
session.php
<?php
session_start();
$_SESSION = array('session1'=>1,'session2'=>2);
echo $_SESSION['session1']; //1
$_SESSION['session1'] = 3;
echo "<pre>";
print_r($_SESSION); //session one now updated to 3
echo "</pre>";
$_SESSION = array();
if ($_SESSION['session1']) {
echo $_SESSION['session1']; // IS NOW EMPTY
} else {
echo "woops... nothing found";
}
?>
<p>
<a href="destroyed.php">NOW GOING TO DESTROYED PHP<a/>
</p>
<?php
session_destroy();
?>
destroyed.php
<?php
session_start(); // calling session start first on destroyed.php
print_r($_SESSION); // prints Array ( )
?>
From the documentation:
If $_SESSION (or $HTTP_SESSION_VARS for PHP 4.0.6 or less) is used,
use unset() to unregister a session variable, i.e. unset ($_SESSION['varname']);
And take care about session_destroy:
session_destroy destroys all of the data associated with the current session. It does not unset any of the global variables associated with the session
Use session_unset(). Like this:
<?php session_start(); ?><!DOCTYPE html>
<html>
<body>
<?php
$_SESSION["variabletounset"] = "I am going to be unset soon along with all of the other session variables.";
print '<pre>' . "\n";
print_r($_SESSION);
print ' </pre>' . "\n";
session_unset();
print ' <pre>' . "\n";
print_r($_SESSION);
print ' </pre>' . "\n";
?>
</body>
</html>
This would output:
Array
(
variabletounset => I am going to be unset soon along with all of the other session variables.
)
Array
(
)
I think this code should echo "first" in first usage and after refresh it should echo timestamp,but it will show first every time,where is my problem?
I set cookie permition on always.
if (isset($_SESSION['TestSession']))
{
echo ($_SESSION['TestSession']);
}
else
{
echo "first";
$_SESSION['TestSession'] = time();
}
Have you placed
session_start();
at the top of your page?
To start a session, first session_start() should be called. Otherwise $_SESSION won't be set, and you will initialize it every time.
I am new to php, and very new to sessions, so I have no idea what I am doing wrong. I followed the tutorial on tizag, and put this code on my site:
<?php
session_start();
echo SID . "<br><br>";
if(isset($_SESSION['views'])) {
$_SESSION['views'] = $_SESSION['views'] + 1;
} else {
$_SESSION['views'] = 1;
echo "views = ". $_SESSION['views'];
}
?>
The SID changes whenever I refresh, and the number does not count up.
Update: Url: http://121.73.150.105/PIA/
FIXED BY: Putting session_start() before my doctype, title etc.
Are cookies enabled in you're browser ? phpsessid is stored as a cookie , you can set different parameters for it , one that could be usefull in you're case could be session_get_cookie_params() , and see if everithing is oki with the session cookie params .
If anything is wrong like expiration date you can set the params with session_set_cookie_params()
Your PHP setup may have been configured to not save sessions in cookies.
To verify if this is the case, you can take a look at session.use_cookies in your php.ini, or using ini_get, like so:
<?php echo ini_get('session.use-cookies'); ?>
You can correct it at runtime, as well, using ini_set, like so:
<?php ini_set('session.use-cookies', '1'); ?>
either you are outputting something to the browser before calling session start, or you have cookies disabled.
You don't output the $_SESSION['view'] after the if statement. I think that's why it doesn't change.
Try:
<?php
session_start();
echo SID . "<br><br>";
if(isset($_SESSION['views'])) {
$_SESSION['views'] = $_SESSION['views'] + 1;
} else {
$_SESSION['views'] = 1;
}
echo "views = ". $_SESSION['views'];
?>
So you always output the new $_SESSION['views'] value.
EDIT:
I think the right answer is that the session is not set. But I'm curious, how can the code always outputs "view = 1"? Can I open a new question referencing this question or just discuss it here?
in your code if you cant see session ID you can write
session_id() in place of SID.
ini_set("session.use_cookies",1);
ini_set("session.use_only_cookies",1);
this two parameter must set to gether if you want it work
First timer to the site, not an overly experienced php programmer here :)
I have a problem, i am using an iframe within a site which im attempting to use a session variable inside, firstly ive just been trying to display the session variable to make sure they are accessible from within the iframe:
echo "session of productcheck ".$_SESSION['productcheck']." ";
echo "session of productcheck1 ".$_SESSION['productcheck1']." ";
echo "session of productcheck2 ".$_SESSION['productcheck2']." ";
echo "session of productcheck3 ".$_SESSION['productcheck3']." ";
this just shows "session of product check" with nothing after each one, I set the session variable as such:
$_SESSION['productcheck'] = $productBox;
the $productBox is a GET from the URL:
echo " <iframe src=\"homeview.php?productBox=$product1\" name=\"FRAMENAME\" width=\"594\" height=\"450\" scrolling=\"No\" id=\"FRAMENAME\" allowautotransparency=\"true\" > </iframe >";
What's strange is if i just take the $productBox variable retrieved from the URL and use that then the code works, its only when i store it in a session variable that it gets confused. I want to retrieve a second $productBox and assign it to session var productcheck1 and so forth down the line. Unfortunately, i have to take one var in at a time, otherwise i could just pass all 4 products and not worry about the sessions.
Perhaps I'm making this far too complicated, any help would be much appreciated Thank you!!
You have to use session_start() in both scripts, the one setting the values (and presumably printing the <iframe>-element?) and the script that produces the contents for the iframe.
e.g. the "outer" script
<?php // test.php
session_start();
$_SESSION['productcheck'] = array();
$_SESSION['productcheck'][] = 'A';
$_SESSION['productcheck'][] = 'B';
$_SESSION['productcheck'][] = 'C';
session_write_close(); // optional
?>
<html>
<head><title>session test</title></head>
<body>
<div>session test</div>
<iframe src="test2.php" />
</body>
</html>
and the script for the iframe content
<?php // test2.php
session_start();
?>
<html>
<head><title>iframe session test</title></head>
<body>
<div>
<?php
if ( isset($_SESSION['productcheck']) && is_array($_SESSION['productcheck']) ) {
foreach( $_SESSION['productcheck'] as $pc ) {
echo $pc, "<br />\n";
}
}
?>
</div>
</body>
</html>
Not sure what's up with your session variables, but you can definitely pass all four variables through the url in your iframe. You just need to separate your key value pairs with an ampersand. So something like this:
file.php?key1=val1&key2=val2&key3=val3 and so on.
This is probably a better way than using session variables if your just trying to get data into that other file.