When I reload my website after uploading it on my webserver, following error is on my website:
Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /data/userfiles/websites/lagersystem/login.php:1) in /data/userfiles/websites/lagersystem/login.php on line 36
I don´t know how to solve this.
This is my source code:
<html>
<head>
<title>Login</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">
<link rel="icon" type="favicon.gif" href="favicon.gif" sizes="256x256">
</head>
<body>
<div class="p-3 mb-2 bg-secondary text-white">
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<a class="navbar-brand" href="index.php"><img src='favicon-64.gif'/></a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarSupportedContent">
<ul class="navbar-nav mr-auto">
<li class="nav-item active">
<a class="nav-link" href="index.php">Home<span class="sr-only">(current)</span></a>
</li>
<li class="nav-item">
<a class="nav-link" href="add.php">Hinzufügen</a>
</li>
<li class="nav-item">
<a class="nav-link" href="login.php">Admin</a>
</li>
</ul>
</div>
</nav>
</div>
<?php
session_start();
$pdo = new PDO('mysql:host=localhost;dbname=', '', '');
if(isset($_GET['login'])) {
$email = $_POST['email'];
$passwort = $_POST['passwort'];
$statement = $pdo->prepare("SELECT * FROM ls_users WHERE email = :email");
$result = $statement->execute(array('email' => $email));
$user = $statement->fetch();
//Überprüfung des Passworts
if ($user !== false && password_verify($passwort, $user['passwort'])) {
$_SESSION['userid'] = $user['id'];
die('<div class="text-center">Login erfolgreich. Weiter zu <a href="sicherheit.php">internen Bereich</a></div>');
} else {
$errorMessage = "E-Mail oder Passwort falsch!<br>";
}
}
?>
<?php
if(isset($errorMessage)) {
echo $errorMessage;
}
?>
<div class="row align-items-center justify-content-center">
<div class="text-center">
<form action="?login=1" method="post">
E-Mail:<br>
<input class="form-control" type="email" size="40" maxlength="250" name="email"><br><br>
Dein Passwort:<br>
<input class="form-control" type="password" size="40" maxlength="250" name="passwort"><br>
<input class="form-control" type="submit" value="Anmelden">
</form>
<br />
<br />
</div>
</div>
<div class="p-3 mb-2 bg-secondary text-white">
<div class="row">
<div class="col">
<div class="text-center">
<a href="index.php" class="btn btn-dark">Aktualisieren</a>
</div>
</div>
<div class="col">
<div class="text-center">
<a href="fehler.php" class="btn btn-danger">Fehlermeldung</a>
</div>
</div>
</div>
</div>
<div class="p-3 mb-2 bg-secondary text-white">
<footer class="mainfooter" role="contentinfo">
<div class="footer-top p-y-2">
<div class="container-fluid">
</div>
</div>
<div class="footer-middle">
<div class="container">
<div class="footer-bottom">
<div class="container">
<div class="row">
<div class="col">
<!--Footer Bottom-->
<p class="text-center">© 2018 - All rights reserved.</p>
</div>
</div>
</div>
</div>
</footer>
</div>
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js" integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js" integrity="sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl" crossorigin="anonymous"></script>
</body>
</html>
Thank you.
