如果用戶名和密碼正確，它將重定向到 profile.php。我在 profile.php 中使用 cookie 來分隔用戶。是否合適？如果沒有，請告訴我如何編碼。如果可能的話我不想使用 get 方法。<?php  include('config.php');  $cookie = isset($_COOKIE['cookie']);  if($cookie) { header('Location: profile.php'); }  else {    echo '<link rel="stylesheet" href="../css/user.css">          <link rel="stylesheet" href="../css/all.css">          <div id="center"><div id="login-area">Login Here<br><br><form method="post">          <i class="fa fa-user"></i>          <input type="text" id="usr-pass" autocomplete="off" placeholder="Username" name="user"><hr><br>          <i class="fa fa-lock"></i>          <input type="password" id="usr-pass" autocomplete="off" placeholder="Password" name="pass"><hr><br>          <input type="submit" id="login" value="Login" name="login">          </form></div></div>    ';    if(isset($_POST['login'])) {      if(!empty($_POST['user']) && !empty($_POST['pass'])) {        $user = $_POST['user'];        $pass = $_POST['pass'];        $query = 'SELECT password FROM user WHERE username = ?';        $stmt = $conn -> prepare($query);        $stmt -> bind_param('s', $user);        $stmt -> execute();        $stmt -> store_result();        if($stmt -> num_rows > 0) {          $stmt -> bind_result($password);          $stmt -> fetch();          if($password == $pass) {            setcookie('cookie', $user);            header('Location: profile.php');          } else { header('Location: login.php'); } //echo 'wrong password';        } else { header('Location: login.php'); } //echo 'account not exist';      } else { header('Location: login.php'); } //echo 'input both username & password';    }  }?>