在我过去几周一直在做的项目的终点线附近，我最近第一次将它上传到我的服务器以检查是否有任何问题。虽然几乎所有东西都完美无瑕，但有一个问题我无法解决这个问题！
说明
这是一个在线商店，用户的购物车存储在$_SESSION['id']变量中。一切都是通过POST请求处理的。单击<input type="submit" name="Submit" value="Add to cart" id="addToCart">按钮后，表单会检查$_SESSION['id']中是否已存在产品ID。如果是这种情况，则会调用break以防止多次添加产品。由于表单的操作指向同一个文件，理论上它应该刷新。为了规避用户在POST请求之后刷新页面/使用后退按钮进行令人讨厌的通知（并且为了防止多次发送表单），我得到了一个帖子/重定向/获取代码片段{{3发帖。正如（我相信）我在one.com上的共享主机运行Apache，我使用了重写方法。
XAMPP上的情况：
访客导航到/sub/0.php（第一个产品的网站），选择他的衣服尺寸并点击添加到购物车。之后，产品ID会附加到$ _SESSION ['id']，页面会在最后刷新?status=success，并在右上角显示一个小购物车。
生产服务器上的情况（已启用错误消息）：
访客导航到/sub/0.php（第一个产品的网站），选择他的衣服尺寸并点击添加到购物车。产品ID被正确附加（我可以检查cart.php并显示），虽然刷新时有EITHER
我的代码出了什么问题，为什么它在XAMPP上运行但在生产服务器上不起作用？ PGR似乎根本不起作用（或者代码永远不会因为调用中断而执行PGR），它也不会在URL后面附加status = success。
我真的很茫然，每一个输入都会非常感激！
以下是产品网站的所有代码：
<?php
session_start();
$id=0;
include (__DIR__."/../includes/php/database.php");
if (isset($_POST['Sumbit'])) {
// echo "submitted";
if (isset($_SESSION['id'])) {
if (gettype($_SESSION['id'])=="string") { //if there are already multiple IDs stored withinSESSION['id'] --> String
for ($i=0; $i < strlen($_SESSION['id']); $i++) {
if ($id == $_SESSION['id'][$i]) { //if there are multiple IDs already in cart and one of them matches with $id (--> multiple items are in the cart, but the current one is not)
echo "<script>alert('Already in Cart!')</script>"; //before implementing PRG, this alert appeared always when trying to add the product twice. Since I implemented PRG, it wasn't triggered once in XAMPP
$alreadyInCart=true;
break;
}
}
if (!isset($alreadyInCart)) { //if already some IDs stored within$_SESSION['id'], but$id is not(--> more than 1 other products are in the cart, but the current one is not)
$_SESSION['id'].=$id;
$_SESSION['size'].=$_POST['Size'];
}
}else{ //if$_STRING['id'] isn't a 'string' (it's an 'integer' --> just one item in the cart), there's no need (nor possibility) to loop.
echo $_SESSION['id'];
if($id==$_SESSION['id']){ //Just one item in cart, but that matches with$id (--> current item already in cart)
$alreadyInCart=true;
echo "<script>alert('Nur 1 Artikel im Warebkorb-Already in Cart!')</script>"; //before implementing PRG, this alert appeared always when trying to add the product twice. Since I implemented PRG, it wasn't triggered once in XAMPP
}else{ //Just 1 item in cart but $id doesn't match with $_SESSION['id'](--> current item not yet in cart)
$_SESSION['id'].=$id;
$_SESSION['size'].=$_POST['Size'];
}
}
}else{ //If $_SESSION['id'] doesn't even exist yet --> = instead of .=
$_SESSION['id']=$id;
$_SESSION['size']=$_POST['Size'];
}
// Post redirect get https://en.wikipedia.org/wiki/Post/Redirect/Get
$get_info = "?status=success";
header("Location: ".$_SERVER['REQUEST_URI'].$get_info);
echo $_GET['status'];
exit();
}
?>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="theme-color" content="#000000" />
<title>CNTRST</title>
<link rel="stylesheet" type="text/css" href="../includes/css/styles1.css">
<link rel="stylesheet" type="text/css" href="../includes/fonts/fonts.css">
<script type="text/javascript" src="https://code.jquery.com/jquery-2.2.0.min.js"></script>
<script type="text/javascript" src="../includes/js/main.js"></script>
<link id="essential" rel="stylesheet" type="text/css" href="../includes/css/sub_styles.css">
<?php
if (isset($_SESSION['id'])) {
if (isset($_GET['status']) && $_GET['status']=="success") {
echo '<script type="text/javascript" src="../includes/js/cart.js"></script>';
}
}
?>
</head>
<body>
<div class="content">
<?php
if (isset($_SESSION['id'])) {
include(__DIR__)."/../includes/php/cart_icon.php";
}
?>
<img id="logo" src="../includes/media/img/icons/logo.svg"></img>
<div class="slideshow">
<img src="../includes/media/img/slideshow/bg.png" id="slideshow_bg">
<img class="slideshow_objects" src="../<?php echo $product->product_image; ?>">
</div>
<div class="description">
<h1><?php echo $product->product_name; ?></h1>
<h2></h2>
<ul>
<?php echo $product->product_desc; ?>
</ul>
<strong id="price"><?php echo $product->product_price; ?> <span class="currency">€</span></strong>
<form action="<?php echo $id ?>.php" method="post">
<fieldset>
<label for="Size">Size</label>
<select name="Size" id="Size">
<option value="0">XS </option>
<option value="1">S </option>
<option value="2">M </option>
<option value="3">L </option>
<option value="4">XL </option>
<option value="5">XXL </option>
</select>
<input type="hidden" name="Product_Name" value="Marble print"><br>
<input type="submit" name="Sumbit" value="Add to cart" id="addToCart">
</fieldset>
</form>
</div>
</div>
<?php include "../includes/php/footer.php" ?>
</div>
</body>
</html>
修改
在代码顶部添加error_reporting(E_ALL); ini_set('display_errors', '1');后，我没有收到空白页，但显示错误消息：
警告：无法修改标头信息 - 已在/ customers / 6中发送的标头（在/customers/6/5/2/cntrst.at/httpd.www/includes/php/database.php:1处开始输出）第40行/5/2/cntrst.at/httpd.www/sub/0.php注意：未定义的索引：/comersomers/6/5/2/cntrst.at/httpd.www/sub/0.php中的状态在第41行
database.php包含：
<?php
ini_set('session.cache_limiter','public');
session_cache_limiter(false);
$host = 'localhost';
$db = 'DB_NAME';
$user = 'root';
$pass = '';
$charset = 'utf8';
$dsn = "mysql:host=$host;dbname=$db;charset=$charset";
$opt = [
PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
PDO::ATTR_EMULATE_PREPARES => false,
];
$con = new PDO($dsn, $user, $pass, $opt);
if (isset($cart)) {
}else{
$product = $con->query("
SELECT * FROM products
WHERE id=$id
");
$product = $product->fetch(PDO::FETCH_OBJ);
}
?>