PHP Login logout example with session



In this login logout example in PHP we used 3 file

login_user.sql

CREATE TABLE `login_user` (
  `id` int(11) NOT NULL,
  `name` varchar(60) NOT NULL,
  `user_name` varchar(20) NOT NULL,
  `password` varchar(20) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

login.php

<?php
    session_start();
    $message="";
    if(count($_POST)>0) {
        $con = mysqli_connect('127.0.0.1:3306','root','','admin') or die('Unable To connect');
        $result = mysqli_query($con,"SELECT * FROM login_user WHERE user_name='" . $_POST["user_name"] . "' and password = '". $_POST["password"]."'");
        $row  = mysqli_fetch_array($result);
        if(is_array($row)) {
        $_SESSION["id"] = $row['id'];
        $_SESSION["name"] = $row['name'];
        } else {
         $message = "Invalid Username or Password!";
        }
    }
    if(isset($_SESSION["id"])) {
    header("Location:index.php");
    }
?>
<html>
<head>
<title>User Login</title>
</head>
<body>
<form name="frmUser" method="post" action="" align="center">
<div class="message"><?php if($message!="") { echo $message; } ?></div>
<h3 align="center">Enter Login Details</h3>
 Username:<br>
 <input type="text" name="user_name">
 <br>
 Password:<br>
<input type="password" name="password">
<br><br>
<input type="submit" name="submit" value="Submit">
<input type="reset">
</form>
</body>
</html>

index.php

<?php
session_start();
?>
<html>
<head>
<title>User Login</title>
</head>
<body>

<?php
if($_SESSION["name"]) {
?>
Welcome <?php echo $_SESSION["name"]; ?>. Click here to <a href="logout.php" tite="Logout">Logout.
<?php
}else echo "<h1>Please login first .</h1>";
?>
</body>
</html>

logout.php

<?php
session_start();
unset($_SESSION["id"]);
unset($_SESSION["name"]);
header("Location:login.php");
?>


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