我正在尝试为学校项目创建一个电子商务网站，该网站从我创建的数据库中获取信息。不幸的是，这是我们获得的部分代码，我无法将商品添加到购物车中以显示在结帐页面。
这是主页代码
<div class="products">
<?php
session_start();
include_once("config.php");
$current_url = urlencode($url="http://".$_SERVER['HTTP_HOST'].$_SERVER['REQUEST_URI']);
$results = $mysqli->query("SELECT product_code, product_name, product_desc, price FROM products");
if($results){
$products_item = '<ul class="products">';
//fetch results set as object and output HTML
while($obj = $results->fetch_object())
{
$products_item .= <<<EOT
<li class="product">
<form method="post" action="cart_update.php">
<div class="product-content"><h3>{$obj->product_name}</h3>
<div class="product-desc">{$obj->product_desc}</div>
<div class="product-info">
Price {$currency}{$obj->price}
<fieldset>
<label>
<span>Quantity</span>
<input type="text" size="2" maxlength="2" name="product_qty" value="1" />
</label>
</fieldset>
<input type="hidden" name="product_code" value="{$obj->product_code}" />
<input type="hidden" name="type" value="add" />
<input type="hidden" name="return_url" value="{$current_url}" />
<div align="center"><button type="submit" class="add_to_cart">Add</button></div>
</div></div>
</form>
</li>
EOT;
}
$products_item .= '</ul>';
echo $products_item;
}
?>
</div>
<div class="shopping-cart">
<?php
if(isset($_SESSION["cart_products"]) && count($_SESSION["cart_products"])>0)
{
echo '<div class="cart-view-table-front" id="view-cart">';
echo '<h3>Your Shopping Cart</h3>';
echo '<form method="post" action="cart_update.php">';
echo '<table width="100%" cellpadding="6" cellspacing="0">';
echo '<tbody>';
$total =0;
foreach ($_SESSION["cart_products"] as $cart_itm)
{
$product_name = $cart_itm["product_name"];
$product_qty = $cart_itm["product_qty"];
$product_price = $cart_itm["product_price"];
$product_code = $cart_itm["product_code"];
echo '<td>Qty <input type="text" size="2" maxlength="2" name="product_qty['.$product_code.']" value="'.$product_qty.'" /></td>';
echo '<td>'.$product_name.'</td>';
echo '<td><input type="checkbox" name="remove_code[]" value="'.$product_code.'" /> Remove</td>';
echo '</tr>';
$subtotal = ($product_price * $product_qty);
$total = ($total + $subtotal);
}
echo '<td colspan="4">';
echo '<button type="submit">Update</button><a href="view_cart.php" class="button">Checkout</a>';
echo '</td>';
echo '</tbody>';
echo '</table>';
$current_url = urlencode($url="http://".$_SERVER['HTTP_HOST'].$_SERVER['REQUEST_URI']);
echo '<input type="hidden" name="return_url" value="'.$current_url.'" />';
echo '</form>';
echo '</div>';
}
?>
</div>
这是更新购物车的php文件
<?php
session_start(); //start session
include_once("config.php"); //include config file
//add product to session or create new one
if(isset($_POST["type"]) && $_POST["type"]=='add' && $_POST["product_qty"]>0)
{
foreach($_POST as $key => $value){ //add all post vars to new_product array
$new_product[$key] = filter_var($value, FILTER_SANITIZE_STRING);
}
//remove unecessary vars
unset($new_product['type']);
unset($new_product['return_url']);
//we need to get product name and price from database.
$statement = $mysqli->prepare("SELECT product_name, price FROM products");
$statement->bind_param('s', $new_product['product_code']);
$statement->execute();
$statement->bind_result($product_name, $price);
while($statement->fetch()){
//fetch product name, price from db and add to new_product array
$new_product["product_name"] = $product_name;
$new_product["product_price"] = $price;
if(isset($_SESSION["cart_products"])){ //if session var already exist
if(isset($_SESSION["cart_products"][$new_product['product_code']])) //check item exist in products array
{
unset($_SESSION["cart_products"][$new_product['product_code']]); //unset old array item
}
}
$_SESSION["cart_products"][$new_product['product_code']] = $new_product; //update or create product session with new item
}
}
//update or remove items
if(isset($_POST["product_qty"]) || isset($_POST["remove_code"]))
{
//update item quantity in product session
if(isset($_POST["product_qty"]) && is_array($_POST["product_qty"])){
foreach($_POST["product_qty"] as $key => $value){
if(is_numeric($value)){
$_SESSION["cart_products"][$key]["product_qty"] = $value;
}
}
}
//remove an item from product session
if(isset($_POST["remove_code"]) && is_array($_POST["remove_code"])){
foreach($_POST["remove_code"] as $key){
unset($_SESSION["cart_products"][$key]);
}
}
}
//back to return url
$return_url = (isset($_POST["return_url"]))?urldecode($_POST["return_url"]):''; //return url
header('Location:'.$return_url);
最后，结帐页面的php文件
<div class="cart-view-table-back">
<form method="post" action="cart_update.php">
<table width="100%" cellpadding="6" cellspacing="0"><thead><tr><th>Quantity</th><th>Name</th><th>Price</th><th>Total</th><th>Remove</th></tr></thead>
<body>
<?php
$total = 0; //set initial total value
if(isset($_SESSION["cart_products"])) //check session var
{
foreach ($_SESSION["cart_products"] as $cart_itm)
{
//set variables to use in content below
$product_name = $cart_itm["product_name"];
$product_qty = $cart_itm["product_qty"];
$product_price = $cart_itm["product_price"];
$product_code = $cart_itm["product_code"];
$subtotal = ($product_price * $product_qty);
echo '<td><input type="text" size="2" maxlength="2" name="product_qty['.$product_code.']" value="'.$product_qty.'" /></td>';
echo '<td>'.$product_name.'</td>';
echo '<td>'.$currency.$product_price.'</td>';
echo '<td>'.$currency.$subtotal.'</td>';
echo '<td><input type="checkbox" name="remove_code[]" value="'.$product_code.'" /></td>';
echo '</tr>';
$total = ($total + $subtotal); //add subtotal to total var
}
}
?>
<tr><td colspan="5"><span style="float:right;text-align: right;">Amount Payable : <?php echo "$".sprintf("%01.2f", $total);?></span></td></tr>
<tr><td colspan="5"><a href="index.php" class="button">Add More Items</a><button type="submit">Update</button></td></tr>
</body>
</table>
<input type="hidden" name="return_url" value="<?php
$current_url = urlencode($url="http://".$_SERVER['HTTP_HOST'].$_SERVER['REQUEST_URI']);
echo $current_url; ?>" />
</form>
</div>
答案 0 :(得分：0)
设法找到了解决方案，
仅需在我的结帐页面php文件中添加session_start（）。