Create simple student management system using PHP with MySQL

Part 1

This tutorial is for php beginners who already known about the fact in php and mysql database syntax. In this Part 1: We are going to create the login.php form to logging into student management website.

login.php

<form action="<?php echo $_SERVER['PHP_SELF'];?>" method="post">
<table>
<tr>
    <td>Username</td>
        <td><input type="text" name="username" /></td></tr>
    <tr>
    <td>Password</td>
<td><input type="password" name="password" /></td></tr>
    <tr>
    <td>&nbsp;</td>
    <td><input type="button" name="btnLogin" value="Login" /></td></tr>        
</table>
</form>


After creating the logging form we have to validate the form using php syntax.
login.php

<?php
$error="";
if(isset($_POST['btnLogin']) and $_POST['btnLogin']="Login")
{

//Process login
$username = $_POST['username'];
$password = $_POST['password'];
include "db.php";
$sql = "select * from user where username='$username'  and password=md5('$password')";
$results  = mysql_query($sql) or die("Error on application: ".mysql_error());
$rowcount = mysql_num_rows($results);
if($rowcount>0)
{
//User Available
session_start();
$_SESSION['user']=$user;
header("Location:index.php");

}  
else
{
//Invalied User 
$error="Invalid Username or Password";
}
}
?>


If you give either wrong username or a password, this page gives an error as Invalid Username or Password.

<form action="<?php echo $_SERVER['PHP_SELF'];?>" method="post">
<table>
<tr>
     <td>Username</td>
        <td><input type="text" name="username" /></td></tr>
    <tr>
     <td>Password</td>
<td><input type="password" name="password" /></td></tr>
    <tr>
     <td>&nbsp;</td>
     <td><input type="button" name="btnLogin" value="Login" /><?php echo $error; ?></td></tr>        
</table>
</form>

Create table called 'user' in your mysql database. Fill password column(remember to set md5 function to your password)

You want to save also the db.php file as well. Here it is.
db.php

<?php
$dbuser = "root";
$dbpassword = "";
$db       = "students";
$host     = "localhost";
$conn = mysql_connect($host,$dbuser,$dbpassword) or die("Unable to connect to the database: ". mysql_error());
mysql_select_db($db) or die("Unable to Select the database: ".mysql_error());
?>



When after giving the username and password correclty you can log into your index page.
index.php

<?php
session_start();
if(isset($_SESSION['user']))
{
?>
#################### BODY ##############


<?php

}

else

{

header("Location:login.php");

}

?>

login.php : see full view

Note: Hope to post Part II soon. Any problem about the application please be kind enough to inform me. Wish you best luck !