javascript - PHP登录脚本重定向在登录后不起作用

Question

我发现并修复了一点，我不太擅长 PHP，但欢迎任何改进。

问题在于，有时在 Chrome 和 Opera 中，但仅有时在登录成功后，脚本会在 5 秒后使用 javascript 重定向重定向到欢迎页面。但有时它只是卡住并且不重定向，而只是显示一个没有错误的白页，而其他时候它会重定向并且工作正常。它可能是什么？

这是代码

<?php session_start();?>
<?php
include 'inc/connection.php';
$db=mysqli_connect($dbserver, $dbuser, $dbpass, $dbname)or die("DB connection error...");

$username_to_sanitize = $_POST['username'];
$password_to_sanitize = $_POST['password'];
$sanitized_username = mysqli_real_escape_string($db, $username_to_sanitize);
$sanitized_password = mysqli_real_escape_string($db, $password_to_sanitize);

$query = "SELECT password, salt, privilege, username FROM members WHERE username = '$sanitize_username'";
$result = mysqli_query($db, $query);
if(mysqli_num_rows($result) == 0) // User not found. Redirected to login page.
{header('Location:login.php?message=Username not found, please try again');}

$userData = mysqli_fetch_array($result, MYSQL_ASSOC);
$hash = hash('sha256', $userData['salt'] . hash('sha256', $sanitized_password) );

if($hash != $userData['password']) // Incorrect passw. Redirected to login page.
{header('Location:error.php?message=Wrong password, please try again');}

else if($userData['privilege']=="ADMIN"){session_start();
$_SESSION['username']=$userData['username'];
header('Location:redirection.php?URL=admins/index.php');}

else if($userData['privilege']=="MODERATOR"){session_start();
$_SESSION['username']=$userData['username'];
header('Location:redirection.php?URL=moderators/index.php');}

else if($userData['privilege']=="MEMBER"){session_start();
$_SESSION['username']=$userData['username'];
header('Location:redirection.php?URL=members/index.php');}

else if($userData['privilegio']=="BANNED"){session_start();
$_SESSION['username']=$userData['username'];
header('Location:redirection.php?URL=banned/index.php');}

else{
header('Location:error.php?message=su need privileges to acces this site');
exit();
}
?>

阅读并测试在互联网上找到的新脚本后，两个月后我仍然无法解决这个问题。有什么想法吗？

Answer 1

你的代码中有很多重复，这很糟糕，因为你重复的每个地方都意味着你更新代码时需要更改它，这意味着以后有更多的地方会出现错误。

为了提供帮助，我只放置了一个 session_start() ，我转换了if/elseif/elseif/elseif...到 switch 语句。

我没有处理位置 header 本身，而是将其替换为 http_redirect function ，这基本上可以为您完成。启动时，它会为您编码 URL，因此您不必担心这一点。

如果您一直看到空白页面，那么您应该检查网络服务器的日志(apache 或 nginx 或 php-fpm 或其他)以查看是否存在错误。否则，打开更好的错误报告；通常空白页只是尚未报告的错误。

<?php 
session_start();
include 'inc/connection.php';
$db = mysqli_connect($dbserver, $dbuser, $dbpass, $dbname) or die('DB connection error...');

$sanitized_username = mysqli_real_escape_string($db, $_POST['username']);
$sanitized_password = mysqli_real_escape_string($db, $_POST['password']);

$query = "SELECT password, salt, privilege, username FROM members WHERE username = '$sanitized_username'";
$result = mysqli_query($db, $query);
if (mysqli_num_rows($result) == 0) {
    // User not found. Redirected to login page.
    http_redirect('login.php', array('message' => 'Username not found, please try again'), true);
}

$userData = mysqli_fetch_array($result, MYSQL_ASSOC);
$hash = hash('sha256', $userData['salt'] . hash('sha256', $sanitized_password) );

if($hash != $userData['password']) {
    // Incorrect passw. Redirected to login page.
    http_redirect('error.php', array('message' => 'Wrong password, please try again'), true);
}
// Just set the username once
$_SESSION['username'] = $userData['username'];

switch ( $userData['privilege'] ) :
    case 'ADMIN':
        http_redirect('redirection.php', array('URL' => 'admins/index.php'), true);
        break;
    case 'MODERATOR' :
        http_redirect('redirection.php', array('URL' => 'moderators/index.php'), true);
        break;
    case 'MEMBER' :
        http_redirect('redirection.php', array('URL' => 'members/index.php'), true);
        break;
    case 'BANNED' :
        http_redirect('redirection.php', array('URL' => 'banned/index.php'), true);
        break;
    default:
        // The message is weird. Should it be:
        // 'You need privileges to access this site' or something like that?
        http_redirect('error.php', array('message' => 'su need privileges to acces this site'), true);
        break;
endswitch;
http_redirect('error.php', array('message' => 'su need privileges to acces this site'), true);
?>