session start not showing username while using email id for login

Question

I have been using the following code for beginning sessions, but I can't show the username after 'welcome'. How can I do that? I am using email and id for logging in. The email, id and username are stored in MySQL. Also when logged in, the login button should disappear, and the logout button should appear.

<div class="hello"> 

<?php  
  session_start();  
  require_once("config.php");  
  if (!(isset($_SESSION['login']) && $_SESSION['login'] != '')) 
  {  
    header ("Location: login.html");  
    exit;  
  }  
  else  
  {  
    echo "Welcome </b>,  <a href=logout.php>Logout</a> <br><br>";  
  }  
?>

</div>

At login, when you're storing `login` in the session, just store `username` too, then just get it from the session where needed...? — Joachim Isaksson, May 11 '13 at 13:10
There's something fishy about `!(isset($_SESSION['login']) && $_SESSION['login'] != '')`. I believe it will always resolve to false.. Cause you are basically saying: IF some part does not exists AND this part is not equal to "". If the first condition is met, the second can never be true. — Jules Colle, May 11 '13 at 13:12

Mooseman · Answer 1 · 2013-05-14T13:12:56.597

1

header() and session_start() must both come before any HTML. You can set $_SESSION['username'] and $_SESSION['email'] where you process the login info.

edited May 14 '13 at 13:12

answered May 11 '13 at 13:12

Mooseman

18,763
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score 1 · Answer 2 · answered May 11 '13 at 13:35

1

As per the php doc :

To use cookie-based sessions, session_start() must be called before outputing anything to the browser.

So remove any HTML or output in your page before session_start() call.

In your case remove from your html.

Or you can use ob_start() in the very first line so that it consumes even any accidental outputs. Even a new line can not be outputted before session_start(). If you are using this method , use ob_clean() method after doing all session (header) related work.

answered May 11 '13 at 13:35

MD. Sahib Bin Mahboob

20,246
2
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okay but how to do formatting of the same like positioning it on the right and with 12px arial verdana, sans-serif font – user2267055 May 11 '13 at 13:56
Sorry , does not understand your problem. If it is not related to this question,please ask a new one then. – MD. Sahib Bin Mahboob May 12 '13 at 05:51

score 1 · Answer 3 · answered May 11 '13 at 14:19

Don't do it like this:

<div class="hello"> 

<?php  
    session_start(); 
    require_once("config.php");

Do it like this:

<?php session_start(); ?>

<div class="hello"> 

<?php  
    require_once("config.php");

session_start() must be called before any output (including whitespace and UTF-8 BOM) are sent to the browser. So the call must be made before anything in any included file gets output. This usually is no problem because a script should not care when the session is started.

score 0 · Answer 4 · answered May 11 '13 at 13:19

You should consider creating a function called get_username_from_email() like so,

<?php

function get_username_from_email($email) {
   $username = mysql_real_escape_string($email);
   return mysql_result(mysql_query("SELECT `username` FROM `YOUR_TABLE` WHERE `email` = '$email'"), 0, 'user_id');
}

?>

In the above code YOUR_TABLE refers to your table name which consists of the essential data.

Then you can perform the following in your existing code:

<?php  
   session_start();  
   require_once("config.php");  
   if (!(isset($_SESSION['login']) && $_SESSION['login'] != '')) 
   {  
      header ("Location: login.html");  
      exit;  
   }  
   else  
   {  
      echo "Welcome". get_username_from_email($_SESSION['login']) ." </b>,  <a href=logout.php>Logout</a> <br><br>";  
   }

?>

However, I'm not quite sure about this.

score 0 · Answer 5 · answered May 11 '13 at 13:20

Let's say you have a username and password field, not when user submits the details, and if it is OK. then, after login, you have to keep his name in the session (I'm not recommending it) but, you could do like this

// if use is verified
$_SESSION['logged'] = $username;

Now, in your sessions file, you can show

echo 'Welcome '.$username.' You, are logged in';

session start not showing username while using email id for login

5 Answers5