checklogin.php

  <?php
    // ob_start();
    include '../include/config.php';
    session_start();
    // Define $myusername and $mypassword
    $myusername=$_POST['myusername'];
    $mypassword=$_POST['mypassword'];

    // To protect MySQL injection
    $myusername = stripslashes($myusername);
    $mypassword = stripslashes($mypassword);
    $myusername = mysql_real_escape_string($myusername);
    $mypassword = mysql_real_escape_string($mypassword);

    // Select database and check login and class
    $sql="SELECT * FROM `members` WHERE username='$myusername' and password='$mypassword'";
    $result=mysql_query($sql);

    // Mysql_num_row is counting table row
    $count=mysql_num_rows($result);

    // If result matched $myusername and $mypassword, table row must be 1 row
      if ($count == 1)  {

        // Overwrite $sql
        $sql="SELECT class, username FROM `members` WHERE username='$myusername' LIMIT 1";
        $result=mysql_query($sql);
        $data=mysql_fetch_array($result);
        $class_number=$data['class'];
        $_SESSION['username'] = $data['username'];
        $_SESSION['class'] = $data['class'];


        if (($class_number == 2) || ($class_number == 6)) {
          session_register("myusername" , "mypassword");
          //$_SESSION['class'] = $data['class'];
          header("location:add.php");
          $_SESSION['username'] = $data['username'];
          $_SESSION['class'] = $data['class'];
        }
        elseif ($class_number == 1) {
          echo "Access denied</br>";
          // header("location:../index.php");
        }
      } else {
        echo "login failed";
      }

  ?>