Login Problem

[newphpcoder]

Good day!

 

I have an index.php or a login page.The scenario on my webpage is when i successfully login and i accidentally press the back button the login page appear again and when i try to login again i could login again, which is not good.

here is my code:

<?php  
session_start(); 
if(isset($_SESSION['USER_ID'])){

exit("you can't login in again when your all ready logged!");

} 
//require_once 'conn.php';  
$db_name="dspi"; 

mysql_connect("localhost", "root", "") or die("Cannot connect to server");
mysql_select_db("$db_name")or die("Cannot select DB");   


        $department = mysql_real_escape_string($_POST['department']);   
        $username = mysql_real_escape_string($_POST['username']); 

        $sql=mysql_query("SELECT `Department`, `Username` FROM `tbllogin` WHERE `Department` = '{$department}' AND Username = '{$username}'") or die(mysql_error()); 
        $ct = mysql_num_rows($sql); 
     
        if($ct == 1) { 
            $row = mysql_fetch_assoc($sql);  
         
            if($row['Department']=='Accounting') { 
                header('location: Company.php'); 
            } elseif($row['Department']=='Engineering') { 
                header('location: Company.php'); 
            } elseif($row['Department']=='Finishing_Goods') { 
                header('location: Company.php'); 
            } elseif($row['Department']=='HRAD') { 
                header('location: Company.php'); 
            } elseif($row['Department']=='MIS') { 
                header('location:Company.php'); 
            } elseif($row['Department']=='Packaging_and_Design') { 
                header('location:Company.php'); 
            } elseif($row['Department']=='Production') { 
                header('location:Company.php'); 
            } elseif($row['Department']=='Purchasing_Logistic') { 
                header('location:Company.php'); 
            } elseif($row['Department']=='QA_and_Technical') { 
                header('location:Company.php'); 
            } elseif($row['Department']=='Supply_Chain') { 
                header('location:Company.php'); 
            } 
            else {
			header('location:index.php');
			echo"Incorrect Username or Department"; 

        	}  
}
?> 

[nblackwood]

I've tried the code you're using, and it works for me. You can always try and have the page automatically log the user out if they go back to the login page. For example:

 

<?php session_start();

 

 

 

if(isset($_SESSION['USER_ID']))

{

unset($_SESSION['USER_ID']);

}

else

{

if(!isset($_SESSION['USER_ID']))

{

$_SESSION['USER_ID'] = '';

header("location:index.php");

}

}

 

?>

 

If that's problematic for you, then I'm out of ideas. Your code should work for you. Hope it helps.