<?php
session_start();

include ('connection.php');

$myusername=$_POST['username'];
$mypassword=$_POST['pass'];

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

$sql="SELECT * FROM register WHERE username='$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){
// Register $myusername, $mypassword and redirect to file "login_success.php"
$_SESSION["myusername"] = $myusername;
$_SESSION["mypassword"] = $mypassword;

header("location:char.php");
}
else {
header("Location:login_fail.html");
}

?>