PHP:点击添加按钮后购物车为空

Question

根据标题，我在将产品添加到购物车时遇到问题:它会显示一条窗口消息，表明该产品已添加，但实际上它不在那里。它给出了以下错误:

Fatal error: Cannot use object of type stdClass as array

the line is: <td><?php echo $value['item_name']; ?></td>

这是代码文件reserve.php:

 <?php

  session_start();
  ini_set('display_errors', 1);
  $connect = mysqli_connect('127.0.0.1', 'root', '***********', 'Community Garden List');


  if (isset($_POST['add'])) {
    if (isset($_SESSION['cart'])) {
        $item_array_id = array_column($_SESSION['cart'], 'product_id');
        if (!in_array($_GET['id'], $item_array_id)) {
            $count = count($_SESSION['cart']);
            $item_array = array(
                'product_id' => $_GET['id'],
                'item_name' => $_POST['hidden_name'],
                'product_price' => $_POST['hidden_price'],
                'item_quantity' => $_POST['quantity'],
            );
            $_SESSION['cart'][$count] = $item_array;
            echo '<script>window.location="reserve.php"</script>';
        } else {
            echo '<script>alert("Product is already Added to Cart")</script>';
            echo '<script>window.location="reserve.php"</script>';
        }
    } else {
        $item_array = array(
            'product_id' => $_GET['id'],
            'item_name' => $_POST['hidden_name'],
            'product_price' => $_POST['hidden_price'],
            'item_quantity' => $_POST['quantity'],
        );
        $_SESSION['cart'][0] = $item_array;
    }
 }

 if (isset($_GET['action'])) {
    if ($_GET['action'] == 'delete') {
        foreach ($_SESSION['cart'] as $keys => $value) {
            if ($value['product_id'] == $_GET['id']) {
                unset($_SESSION['cart'][$keys]);
                echo '<script>alert("Product has been Removed...!")</script>';
                echo '<script>window.location="reserve.php"</script>';
            }
        }
    }
 }
 ?>

    ?>

html代码

 <?php

     $query = 'SELECT * FROM product ORDER BY serial ASC';
     $result = mysqli_query($connect, $query);

     if (mysqli_num_rows($result) > 0) {
         while ($row = mysqli_fetch_array($result)) {
             ?>
             <div class="col-md-4">
            <form method="post" action="reserve.php?action=add&id='.$row['id'].">
            <div style="border: 1px solid #eaeaec; margin: -1px 19px 3px -1px; box-shadow: 0 1px 2px rgba(0,0,0,0.05); padding:10px;" align="center">

                <img src="<?php echo $row['image']; ?>" class="img-responsive" style="width:100%;>
            <h5 class="text-info"><?php echo $row['pname']; ?></h5>
            <h5 class="text-danger">€ <?php echo $row['price']; ?></h5>
            <h5 class="text-info"><?php echo $row['pdescription']; ?></h5>
            <input type="text" name="quantity" class="form-control" value="1">
            <input type="hidden" name="hidden_name" value="<?php echo $row['pname']; ?>">
            <input type="hidden" name="hidden_price" value="<?php echo $row['price']; ?>">
            <input type="hidden" name="hidden_pdescription" value="<?php echo $row['pdescription']; ?>">
            <input type="submit" name="add" style="margin-top:5px;" class="btn btn-success" value="Add to Bag">
            </div>
            </form>
            </div>
                }
        }
        ?>

 <?php
                if(!empty($_SESSION["cart"])){
                    $total = 0;
                    foreach ($_SESSION["cart"] as $key => $value) {
                        ?>
                        <tr>
                            <td><?php echo $value["item_name"]; ?></td>
                            <td><?php echo $value["item_quantity"]; ?></td>
                            <td>$ <?php echo $value["product_price"]; ?></td>
                            <td>
                                $ <?php echo number_format($value["item_quantity"] * $value["product_price"], 2); ?></td>
                            <td><a href="Cart.php?action=delete&id=<?php echo $value["product_id"]; ?>"><span
                                        class="text-danger">Remove Item</span></a></td>

                        </tr>
                        <?php
                        $total = $total + ($value["item_quantity"] * $value["product_price"]);
                    }
                        ?>
                        <tr>
                            <td colspan="3" align="right">Total</td>
                            <th align="right">$ <?php echo number_format($total, 2); ?></th>
                            <td></td>
                        </tr>
                        <?php
                    }
                ?>
            </table>
        </div>

    </div>

我已经尝试过print "<pre>"; var_dump($row); exit;此行之后:foreach e($_SESSION['cart'] as $key => $value) {它有一张 table ，上面有 NULL里面。这是什么意思？

在此之前，我尝试更改$value['item_name']与 $value->item_name ，我收到以下错误:

Notice: Undefined property: stdClass::$item_name in

您能帮助我了解问题所在吗？谢谢。

Answer 1

我解决了一些错误，尝试将零件组装在正确的位置我把修改的所有内容都放在这里你应该复制粘贴你需要的部分。

<?php

  session_start();
  ini_set('display_errors', 1);
  $connect = mysqli_connect('127.0.0.1', 'root', '******************', 'Community Garden List');


  if (isset($_POST['add'])) {
    if (isset($_SESSION['cart'])) {
        $item_array_id = array_column($_SESSION['cart'], 'product_id');
        if (!in_array($_GET['id'], $item_array_id)) {
            $count = count($_SESSION['cart']);
            $item_array = array(
                'product_id' => $_GET['id'],
                'item_name' => $_POST['hidden_name'],
                'product_price' => $_POST['hidden_price'],
                'item_quantity' => $_POST['quantity']//!!!,
            );
            $_SESSION['cart'][$count] = $item_array;
            //echo '<script>window.location="reserve.php"</script>';//   do not send content when you use sessions $_SESSION['cart'][0] = $item_array;
        } else {
           // echo '<script>alert("Product is already Added to Cart")</script>';
            //echo '<script>window.location="reserve.php"</script>';
        }
    } else {
        $item_array = array(
            'product_id' => $_GET['id'],
            'item_name' => $_POST['hidden_name'],
            'product_price' => $_POST['hidden_price'],
            'item_quantity' => $_POST['quantity']//!!!!!!!!!!!!  ?  ->,
        );
        $_SESSION['cart'][0] = $item_array;
    }
 }

 if (isset($_GET['action'])) {
    if ($_GET['action'] == 'delete') {
        foreach ($_SESSION['cart'] as $keys => $value) {
            if ($value['product_id'] == $_GET['id']) {
                unset($_SESSION['cart'][$keys]);
                echo '<script>alert("Product has been Removed...!")</script>';
                echo '<script>window.location="reserve.php"</script>';
            }
        }
    }
 }


     $query = 'SELECT * FROM product ORDER BY serial ASC';
     $result = mysqli_query($connect, $query);

     if (mysqli_num_rows($result) > 0) {
         while ($row = mysqli_fetch_array($result)) {
             die();
$tmimi1=<<<mimi1
<div class="col-md-4">
<form method="post" action="reserve.php?action=add&id={$row['id']}">
<div style="border: 1px solid #eaeaec; margin: -1px 19px 3px -1px; box-shadow: 0 1px 2px rgba(0,0,0,0.05); padding:10px;" align="center">

<img src="{$rr1}" class="img-responsive" style="width:100%;">
<h5 class="text-info">{$row['pname']}</h5>
<h5 class="text-danger">€{$row['price']}</h5>
<h5 class="text-info">{$row['pdescription']}</h5>
<input type="text" name="quantity" class="form-control" value="1">
<input type="hidden" name="hidden_name" value="{$row['pname']}">
<input type="hidden" name="hidden_price" value="{$row['price']}">
<input type="hidden" name="hidden_pdescription" value="{$row['pdescription']}">
<input type="submit" name="add" style="margin-top:5px;" class="btn btn-success" value="Add to Bag">
</div>
</form>
</div>
mimi1;
         }
}
echo($tmimi1);
                if(!empty($_SESSION["cart"])){
                    $total = 0;
                    foreach ($_SESSION["cart"] as $key => $value) {
$tmimi2 =<<<mimi2
                        <tr>
                            <td>{$value["item_name"]}</td>
                            <td>{$value["item_quantity"]}</td>
                            <td>${$value["product_price"]}</td>
                            <td>$
mimi2;
echo($tmimi2);
echo number_format($value["item_quantity"] * $value["product_price"], 2);

$tmimi2=<<<mimi3
</td>
                            <td><a href="Cart.php?action=delete&id={$value["product_id"]}"><span
                                        class="text-danger">Remove Item</span></a></td>

                        </tr>
mimi3;
echo($tmimi3);
                        $total = $total + ($value["item_quantity"] * $value["product_price"]);
                    }
$tmimi2=<<<mimi4
                        <tr>
                            <td colspan="3" align="right">Total</td>
                            <th align="right">$ 
mimi4;
echo($tmimi4);
echo number_format($total, 2); 
$tmimi2=<<<mimi5
</th>
                            <td></td>
                        </tr>
mimi5;
echo($tmimi5);                    }
$tmimi2=<<<mimi6
            </table>
        </div>

    </div>
mimi6;
echo($tmimi6);
?>