Untitled

<?php include "base.php"; ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>User Management System (Tom Cameron for NetTuts)</title>
<link rel="stylesheet" href="style.css" type="text/css" />
</head>
<body>
<div id="main">
<?php
if(!empty($_POST['username']) && !empty($_POST['password']))
{
	$username = mysql_real_escape_string($_POST['username']);
    $password = md5(mysql_real_escape_string($_POST['password']));
    $email = mysql_real_escape_string($_POST['email']);
	$sa = mysql_real_escape_string($_POST['sa']);

	 $checkusername = mysql_query("SELECT * FROM users WHERE Username = '".$username."'");

     if(mysql_num_rows($checkusername) == 1)
     {
     	echo "<h1>Error</h1>";
        echo "<p>Sorry, that username is taken. Please go back and try again.</p>";
     }
     else
     {
     	$registerquery = mysql_query("INSERT INTO users (Username, Password, EmailAddress, SA) VALUES('".$username."', '".$password."', '".$email."', '".$sa."')");
        if($registerquery)
        {
        	echo "<h1>Success</h1>";
        	echo "<p>Your account was successfully created. Please <a href=\"index.php\">click here to login</a>.</p>";
        }
        else
        {
     		echo "<h1>Error</h1>";
        	echo "<p>Sorry, your registration failed. Please go back and try again.</p>";
        }
     }
}
else
{
	?>

   <h1>Register</h1>

   <p>Please enter your details below to register.</p>

	<form method="post" action="register.php" name="registerform" id="registerform">
	<fieldset>
		<label for="username">Username:</label><input type="text" name="username" id="username" /><br />
		<label for="password">Password:</label><input type="password" name="password" id="password" /><br />
        <label for="email">Email Address:</label><input type="text" name="email" id="email" /><br />
		<label for="sa">Name of your junior high school:</label><input type="text" name="sa" id="sa" /><br />
		<input type="submit" name="register" id="register" value="Register" />
	</fieldset>
	</form>

   <?php
}
?>
</div>
</body>
</html>