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// INDEX

<?php
   define('DB_SERVER', 'localhost');
   define('DB_USERNAME', 'root');
   define('DB_PASSWORD', '');
   define('DB_DATABASE', 'logindaten');
   $db = mysqli_connect(DB_SERVER,DB_USERNAME,DB_PASSWORD,DB_DATABASE) or die ("ERROR");

   if($_SERVER["REQUEST_METHOD"] == "POST") {
      // username and password sent from form

      $myusername = mysqli_real_escape_string($db,$_POST['username']);
      $mypassword = mysqli_real_escape_string($db,$_POST['password']);

      $sql = "SELECT * FROM user WHERE Name = '$myusername' and Password = '$mypassword'";
      $result = mysqli_query($db,$sql);
      $row = mysqli_fetch_array($result,MYSQLI_ASSOC);
      $active = $row['active'];

      $count = mysqli_num_rows($result);

      if($count == 1) {
         $_SESSION['login_user'] = $myusername;

         header("location: Welcome.php");
      }else {
		 header("location: Login.html");
      }
   }
?>
//Logout
<?php
   session_start();

   if(session_destroy()) {
      header("Location: Login.html");
   }
?>

//Welcome
<html>
   <head>
      <title>Welcome </title>
   </head>

   <body>
      <h1>Welcome </h1>
      <h2><a href = "Logout.php">Sign Out</a></h2>
   </body>

</html>