PHP - Checking If 1 Session Is Active If Not, The Other Session.

in this page
 http://maximaart.com/newscp/
i have this problem
Code: [Select]
Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at /home/maximasy/public_html/newscp/index.php:1) in /home/maximasy/public_html/newscp/index.php on line 2

my source code is

<?php
session_start();
include_once("config.php"); 
include_once("functions.php");
$errorMessage = '';
if (isset($_POST['txtUserId']) && isset($_POST['txtPassword'])) {
if ($_POST['txtUserId'] === "$user" && $_POST['txtPassword'] === "$pass") {
// the user id and password match,
$_SESSION['basic_is_logged_in'] = true;
require("main.php");
exit;?>

I am trying to create an index page which contains registration and login field
the problem that i get is on successful login a warning is displayed
session_start() [function.session-start]: Cannot send session cookie - headers already sent by (output started at C:\xampp\htdocs\Eventz.com\index.php:116) in C:\xampp\htdocs\Eventz.com\index.php on line 235

This is the login part of my index.php
this tag is inside an html table below the login form
I also have a registration form and its php code above the login form


Code: [Select]
<?php
if (isset($_REQUEST['pass']))
{
    $id=$_POST['id'];
    $pass=$_POST['pass'];

    $conn =mysql_connect("localhost","root","");
    if (!$conn)
    {
   die('Could not connect: ' . mysql_error());
    }
/*
checking connection....success!
*/
    $e=mysql_select_db('test', $conn);
    if(!$e)
    {
   die(''.mysql_error());
    }
    else
    {
   echo 'database selected successfully';
    }

    if (isset($_REQUEST['id'])  || (isset($_REQUEST['pass'])))
    {
        if($_REQUEST['id'] == "" || $_REQUEST['pass']=="")
        {
       echo "login fields cannot be empty";
        }
        else
        {
            $sql=mysql_query("Select email,password from login where email='$id' AND password='$pass'");
            $count=mysql_num_rows($sql);
            if($count==1) 

    /* $count checks if username and password are in same row */
            {   
                session_start();
                $_SESSION['id']=$id;
                echo "</br>Login Successful</br>";
            }
            else
            {
           echo "</br>invalid</br>";
           echo "please try to login again</br>";

            }
        
        }   
    }
}
?>


Any help or suggestion would be appreciated

I'm making a simple login system with MySQL and PHP (very simple, I'm just starting with PHP). The MySQL portion is done, but I need to ensure only people who are logged in can see certain content.

To check if people are logged in, my website checks that they have the $_SESSION['user'] variable set. If it is set, then it lets them continue through the website, if not, it tells them to login. Is that enough security, or can people simply inject a session cookie into their browser to spoof that they are logged in?

My idea was to generate a session key cookie when they login (just a random string of letters and numbers) and store that in the database, then on every page, check to make sure their session key is the same thing that's in the database. Is this necessary? It seems expensive.

hi everyone.

i'm wondering what the best way is to create a session variable and pass it to an iframe.
i need to do something along these lines, but it doesn't seem to pass the ID. Any hints on how i should accomplish this?

Code: [Select]
session_start();
  $_SESSION['ID']=$_GET['ID']; // id from previous page
$ID=session_id();

 <iframe src="iframepage.php?ID=<?php echo $ID; ?>" style="width:680px; height:200px;" noresize="noresize" frameborder="0" border="0" scrolling="Yes" allowtransparency="true" /> </iframe>

Just curious how other people feel about this.  I am working on an application where a lot of info is pulled from MySQL and needed on multiple pages.     Would it make more sense to...   1.  Pull all data ONCE and store it in SESSION variables to use on other pages    2.  Pull the data from the database on each new page that needs it   I assume the preferred method is #1, but maybe there is some downside to using SESSION variables "too much"?   Side question that's kind of related:  As far as URLs, is it preferable to have data stored in them (i.e. domain.com/somepage.php?somedata=something&otherdata=thisdata) or use SESSION variables to store that data so the URLs can stay general/clean (i.e. domain.com/somepage.php)?   Both are probably loaded questions but any possible insight would be appreciated.   Thanks! Greg
Edited by galvin, 04 November 2014 - 10:30 AM.

I am producing a php script which will include some AJAX in the resultant web page, which will send some data to another php script for processing.

If I create a php session in my original script, will the same session be accessed by the second script being run by the AJAX or will it create a new session?

Code: [Select]
<?php

session_start();
if(!session_is_registered(myusername)){
header("location:./default.php");
}

?>

My session works fine but I am just wondering how I can echo the current sessions username?

Thanks

People please help me i beg you, been trying to do this same thing for the past 4hours (-) close to giving up on php and learning a new languages :S

Well as I was updating my login/sign up because its old and it was not very safe.

Now my session are not working, well they work when i set them but it wont destroy so you cant log out. I have tryed doing 100 ways but i get one error or another or it dont work out all.

login page

<?php session_start();

require_once "../config.php"; ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>



<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Admin CP</title>





<?php

$flag=0;
if(isset($_POST['Submit']))
{
$con = database_connect();


$username = $_POST['username'];
$password = $_POST['password'];
clean($username);
clean($password);
$username = mysql_real_escape_string($username);
$password = mysql_real_escape_string($password);
mysql_close($con);
$md5password= md5($password);

database_connect();

$sql="select * from $membertables WHERE username='$username' and password='$md5password' and (userlevel='1' or userlevel='2') ";
$res=mysql_query($sql);
if(!$res)
{
die('error in database');
}
$row=mysql_fetch_array($res);
if(mysql_num_rows($res)>0)
{

$_SESSION['logged_in'] ="loggedin";
$_SESSION['userid']=$row['uid'];
$_SESSION['username']=$row['username'];
$_SESSION['userlevel']=$row['userlevel'];
session_write_close();
header('location:welcome.php');
}
else
{
$_SESSION['logged_in'] = "notloggedin";
$flag=1;
}
}
?>


 
<script language="javascript">
function valid()
{
if(document.frm1.txtuname.value=="")
{
alert('Enter User-ID');
document.frm1.txtuname.focus();
return false;
}
if(document.frm1.txtpass.value=="")
{
alert('Enter Password');
document.frm1.txtpass.focus();
return false;
}
}
</script>


<!-- CSS -->
<link href="style/css/transdmin.css" rel="stylesheet" type="text/css" media="screen" />
<!--[if IE 6]><link rel="stylesheet" type="text/css" media="screen" href="style/css/ie6.css" /><![endif]-->
<!--[if IE 7]><link rel="stylesheet" type="text/css" media="screen" href="style/css/ie7.css" /><![endif]-->

<!-- JavaScripts-->
<script type="text/javascript" src="style/js/jquery.js"></script>
<script type="text/javascript" src="style/js/jNice.js"></script>
</head>

<body>

<div id="wrapper">
    

<!-- h1 tag stays for the logo, you can use the a tag for linking the index page -->
    

<h1><a href="#"><span>Transdmin Light</span></a></h1>
        
        <!-- You can name the links with lowercase, they will be transformed to uppercase by CSS, we prefered to name them with uppercase to have the same effect with disabled stylesheet -->
        <ul id="mainNav">
        

<li></li> 
        

<!-- Use the "active" class for the active menu item  -->
        

<li></li>
        

<li></li>
        

<li class="logout"></li>
        </ul>
        <!-- // #end mainNav -->
        
  <div id="containerHolder">

<div id="container"><!-- // #sidebar -->

                <!-- h2 stays for breadcrumbs -->
              <h2>Login &raquo;</h2>
                
              <div id="main">
              
              
                  <form action="index.php" method="post" name="frm1" id="frm1" onSubmit="return valid();">

                <table width="100%" border="0" cellpadding="0" cellspacing="0"">
                 
                    
                    <tr>
                      <td align="left"><table border="0" cellpadding="5" cellspacing="1" width="576">
                       
                       
                        <tbody>
                          <tr>
                            <td colspan="2" align="center"><br />
                              Please enter your User Name and password below.<br /></td>
                          </tr>
                          
                          
                          
                          <?php   if($flag==1)  {  ?>
                          <tr>
                            <td width="333" align="center" style="background-color: #F00; text-decoration: underline; color: #FF0;" ><p>Enter Valid User-Name or Password </p></td>
                          </tr>
                          
                          
                          
                          <?php

}

?>
                          
                          
                          
                          <tr>
                            <td align="right" >User Name:</td>
                            <td width="344"><input style="background-color: rgb(221, 234, 248);" class="form_text" id="username" name="username" />
                            <script language="JavaScript" type="text/javascript">document.getElementById('txtuname').focus(); </script></td>
                          </tr>
                          
                          
                          <tr>
                            <td align="right">Password:</td>
                            <td><input class="form_text" id="password" name="password" type="password" /></td>
                          </tr>
                          
                          
                          <tr>
                            <td>&nbsp;</td>
                            <td> <input class="buttons" value="sign me in" name="Submit" type="submit" id="Submit" /> </td>
                          </tr>
                          
                          <tr>
                            <td style="height: 30px;">&nbsp;</td>
                            <td>&nbsp;</td>
                          </tr> 
                           
                      </table>
                      </td>
                    </tr>
                 </tbody>
                </table>
             
                </form>
              </div>
                <!-- // #main -->
                
              <div class="clear"></div>
            </div>
            <!-- // #container -->
        </div>

        <!-- // #containerHolder -->
        
        <p id="footer"><?php echo $footer ?></p>
    </div>
    <!-- // #wrapper -->
</body>
</html>





<?php
session_start();
if($_SESSION['logged_in']="loggedin");
else{

 header('location:index.php');
}

?>





sign out page

<?php
session_start();

session_unset();
session_destroy();
header('location:index.php');
?>

what is the problem here?


$sql="INSERT INTO comment (linkid, text, anvid)
VALUES
('$_POST[link]','$_POST[comment]','$_SESSION['user'];')";

Why is my SESSION not getting set in the code below?!

Code: [Select]
<?php
// Initialize a session.
session_start();

// Initialize Logged-In Status.
$_SESSION['loggedIn'] = FALSE;

// Display Logged-In Status.
echo '<p>$_SESSION[\'loggedIn\'] = ' . $_SESSION['loggedIn'] . '</p>';

exit();

When I run this I get...

$_SESSION['loggedIn'] =


Debbie

I am building an app (PHP and MySQL)and I had been using a lot of GET calls to get info from URLs, but the more I thought about it, the more I didn't like the possibility of people being able to mess with the URLs.  So I am in the process of changing everything to use SESSION variables to store data across pages, rather than GET.   The way I see it, SESSION variables are completely behind the scenes so they seem to be the better option.  Am I right, or is GET better than SESSION for some reason?

Firstly, I am new to the forum, so hello 

I am trying to code a login script for my website. I have got the login to work but how do I get it to create a session so the user stays logged in until they log out?

Also how can I prevent access to success.php and fail.php so they cannot be accessed directly. I am new to PHP so please explain in detail for me.

Here is my code...

Code: [Select]
<?php
ob_start();
$host=""; // Host name 
$username=""; // Mysql username 
$password=""; // Mysql password 
$db_name=""; // Database name 
$tbl_name=""; // Table name

mysql_connect("$host", "$username", "$password")or die("cannot connect"); 
mysql_select_db("$db_name")or die("cannot select DB");
 
$myusername=$_POST['myusername']; 
$mypassword=$_POST['mypassword'];
$mypassword=md5($mypassword);

$myusername = stripslashes($myusername);
$mypassword = stripslashes($mypassword);
$myusername = mysql_real_escape_string($myusername);
$mypassword = mysql_real_escape_string($mypassword);

$sql="SELECT * FROM $tbl_name WHERE email='$myusername' and password='$mypassword'";
$result=mysql_query($sql);

$count=mysql_num_rows($result);

if($count==1){
session_register("myusername");
session_register("mypassword"); 
header("location:success.php");
}
else {
header("location:fail.php");
}

ob_end_flush();
?>

How to add more data into $_SESSION? I have following code:
Code: [Select]
if(isset($_GET['poredi']) && $_GET['poredi'] == "upo"){
$idp = intval($_POST['idp']);
$sql = "SELECT * FROM product
WHERE product_id={$idp}";
$query=mysql_query($sql);
if(mysql_num_rows($query)!=0){
$row=mysql_fetch_array($query);
$_SESSION['poredi'] = $row['product_id'];

}
}

On click it need to store more product_id, and after that i have to be able to do query with data (find all data with product_id)?

hello all,

What I want to do is, make the session ID clickable in a url here

Code: [Select]
Login Successful <a href="user.php">Conitnue</a>

so when a user logs in, his ID gets in the link of Continue so he can only see his information

so for example, if his id is 10, then the url would be ....user.php?id=10

Hi,
I am trying to get the value of a session veriable and if the variable contains a certain word it will show an error message, else just continue as normal.


if (isset($_POST['selectroom']))
{$_SESSION['room'] = $_POST['selectroom'];}
if (!isset($_SESSION['room']))
$room = "RoomNameA";
else
$room = $_SESSION['room'];


Please Advise,
 - Stuart