Question

我的问题是，当我在向其添加产品后尝试访问我的购物车时，我一直收到同样的错误，

“mysqli_num_rows（）期望参数1为mysqli_result，boolean 给定的“

使用这行代码：

$ itemnumrows = mysqli_num_rows（$ itemsresult）;

<?php
function showcart()
{
    require('connect.php');
    if (isset($_SESSION['SESS_ORDERNUM'])) {
        if (isset($_SESSION['SESS_LOGGEDIN'])) {
            $custquery = "SELECT id, status from orders WHERE customer_id = " . $_SESSION['SESS_USERID'] . " AND status < 2;";
            $custresult = mysqli_query($con, $custquery);
            $custrow = mysqli_fetch_assoc($custresult);
            $itemsquery = "SELECT products.*, orderitems.*, orderitems.id AS itemid FROM products, orderitems WHERE orderitems.product_id =products.id AND order_id = " . $custrow['id'];
            $itemsresult = mysqli_query($con, $itemsquery);
            $itemnumrows = mysqli_num_rows($itemsresult);
        } else {
            $custquery = "SELECT id, status from orders WHERE session = '" . session_id() . "' AND status < 2;";
            $custresult = mysqli_query($con, $custquery);
            $custrow = mysqli_fetch_assoc($custresult);
            $itemsquery = "SELECT products.*, orderitems.*, orderitems.id AS itemid FROM products, orderitems WHERE orderitems.product_id = products.id AND order_id = " . $custrow['id'];
            $itemsresult = mysqli_query($con, $itemsquery);
            $itemnumrows = mysqli_num_rows($itemsresult);
        }
    } else {
        $itemnumrows = 0;
    }
    if ($itemnumrows == 0) {
        echo "You have not added anything to your shopping cart yet.";
    } else {
        echo "<table cellpadding='10'>";
        echo "<tr>";
        echo "<td></td>";
        echo "<td><strong>Item</strong></td>";
        echo "<td><strong>Quantity</strong></td>";
        echo "<td><strong>Unit Price</strong></td>";
        echo "<td><strong>Total Price</strong></td>";
        echo "<td></td>";
        echo "</tr>";
        while ($itemsrow = mysqli_fetch_assoc($itemsresult)) {
            $quantitytotal = $itemsrow['price'] * $itemsrow['quantity'];
            echo "<tr>";
            if (empty($itemsrow['image'])) {
                echo "<td><img src='productimages/dummy.jpg' width='50' alt='" . $itemsrow['name'] . "'></td>";
            } else {
                echo "<td><img src='productimages/" . $itemsrow['image'] . "' width='50' alt='" . $itemsrow['name'] . "'></td>";
            }
            echo "<td>" . $itemsrow['name'] . "</td>";
            echo "<td>" . $itemsrow['quantity'] . "</td>";
            echo "<td><strong>&pound;" . sprintf('%.2f', $itemsrow['price']) . "</strong></td>";
            echo "<td><strong>&pound;" . sprintf('%.2f', $quantitytotal) . "</strong></td>";
            echo "<td>[<a href='delete.php?id=" . $itemsrow['itemid'] . "'>X</a>]</td>";
            echo "</tr>";
            @$total = $total + $quantitytotal;
            $totalquery = "UPDATE orders SET total = " . $total . " WHERE id = " . $_SESSION['SESS_ORDERNUM'];
            $totalresult = mysqli_query($con, $totalquery);
        }
        echo "<tr>";
        echo "<td></td>";
        echo "<td></td>";
        echo "<td></td>";
        echo "<td>TOTAL</td>";
        echo "<td><strong>&pound;" . sprintf('%.2f', $total) . "</strong></td>";
        echo "<td></td>";
        echo "</tr>";
        echo "</table>";
        echo "<p><a href='checkout.php'>Go to the checkout</a></p>";
    }
}

?>

继承我的showcart页面，同样的错误：

$ numrows = mysqli_num_rows（$ result）;

<?php
session_start();
require("header.php");
require("functions.php");
echo "<h1>Your shopping cart</h1>";
showcart();
if (isset($_SESSION['SESS_ORDERNUM']) == TRUE) {
    $query = "SELECT * FROM orderitems WHERE order_id = " . $_SESSION['SESS_ORDERNUM'] . ";";
    $result = mysqli_query($con, $query);
    $numrows = mysqli_num_rows($result);
    if ($numrows >= 1) {
        echo "<h2><a href='checkout.php'>Go to the checkout</a></h2>";
    }
}
require("footer.php");
?>

我的页眉页面，当我点击viewcart链接时，它会输出与上面的代码块相同的错误..

<?php
if (!isset($_SESSION)) {
    session_start();
}
if (isset($_SESSION['SESS_CHANGEID']) == TRUE) {
    session_unset();
    session_regenerate_id();
}
include("connect.php");
?>
<html>
<head>
    <link rel="stylesheet" href="css/style.css">
</head>
<body>

<div id="header">
    <h1 style="color:#ffffff"> <?php echo $site; ?> </h1>
</div>
<div id="menu">
    <a href="<?php echo $access; ?>">Home</a>
    <a href="showcart.php">View Basket/Checkout</a></div>
<div id="container">
    <div id="bar">
        <?php
        include("bar.php");
        echo "<hr />";
        if (isset($_SESSION['SESS_LOGGEDIN']) == TRUE) {
            echo "Logged in as <strong>'" . $_SESSION['SESS_USERNAME'] . "'</strong>[<a href='" . $access . "logout.php'>logout</a>]";
        } else {
            echo "<a href='" . $access . "login.php'>Login</a>";
        } ?></div>
    <div id="main">

将产品添加到购物车会导致错误

0 个答案: