php登錄會話處理問題

Question

這是我的登錄表單php代碼。據我所知，這段代碼沒問題，但會話處理存在問題。我認爲在我的代碼中沒有會話創建。但無法看到任何錯誤當然我研究了許多資源，證明了這一點。必須讚賞任何幫助。

主頁 -

<?php 

session_start(); 
session_regenerate_id(); 
if(!isset($_SESSION['user']))  // if there is no valid session 
{ 
    header("Location: login.html?action=no"); 
die(); 
} else { 

} 
?> 

登錄頁面（的index.php） -

<?php 

if(isset($_POST['submit'])) 
{ 
    $dbHost = "localhost";  //Location Of Database usually its localhost 
    $dbUser = "root";   //Database User Name 
    $dbPass = "";   //Database Password 
    $dbDatabase = "testdb"; //Database Name 

    $db = mysql_connect($dbHost,$dbUser,$dbPass)or die("Error connecting to database."); 
    //Connect to the databasse 
    mysql_select_db($dbDatabase, $db)or die("Couldn't select the database."); 
    //Selects the database 

    /* 
     The Above code can be in a different file, then you can place include'filename.php';  instead. 
    */ 

    //Lets search the databse for the user name and password 
    //Choose some sort of password encryption, I choose sha256 
    //Password function (Not In all versions of MySQL). 
    $usr = mysql_real_escape_string($_POST['username']); 
    $pas = hash('sha256', mysql_real_escape_string($_POST['password'])); 
    $sql = mysql_query("SELECT * FROM users_table 
     WHERE username='$usr' AND 
     password='$pas' 
     LIMIT 1"); 
    session_start(); 
    if(isset($_POST['username']) && isset($_POST['password'])) 
    { 
     if(auth($_POST['username'], $_POST['password'])) 
     { 
      // auth okay, setup session 
      $_SESSION['user'] == $_POST['username']; 
      isset($_SESSION['user']); 
      session_register("user"); 
      // redirect to required page 
      $Groups = $result["Groups"]; 

      if($Group == 'a') 
      { // "Admin" 
       $_SESSION['user'] == $_POST['username']; 
       isset($_SESSION['user']); 
       session_register("user"); 
       header("Location: video.html"); 
      } elseif($Group == 'admin') { 
       $_SESSION['user'] == $_POST['username']; 
       isset($_SESSION['user']); 
       session_register("user"); 
       header("Location: home.html"); 
      } else { 
       // didn't auth go back to loginform 
       header("Location: index.html"); 
      } 
     } 
    } 

?> 

Answer 1

$_SESSION['user'] == $_POST['username']; 

應該

$_SESSION['user'] = $_POST['username'];