我试图将产品添加到购物车中，但循环逻辑有一些问题。此功能应添加新产品，并检查产品id是否已在购物车中。如果它在购物车中，它应该在现有产品或用户选择的数量上添加1。这是我的一些代码：
function AddToCart($pid, $q)
{
$quantity = $q;
$product_id = $pid;
if (is_array($_SESSION['products']))
{
foreach($_SESSION['products'] as $key => $my_value)
{
if ($pid === $my_value['product_id'])
{
if ($quantity != 1)
{
$quantity = $my_value['quantity'] + $quantity;
$_SESSION['products'][$key]['quantity'] = $quantity;
}
else
{
$quantity = $my_value['quantity'] + 1;
$_SESSION['products'][$key]['quantity'] = $quantity;
}
}
else
{
$_SESSION['products'][] = array(
'product_id' => $product_id,
'quantity' => $quantity,
);
}
}
}
else
{
$_SESSION['products'][] = array(
'product_id' => $product_id,
'quantity' => $quantity,
);
}
}
$_SESSION的var_dump如下所示：
array(8) {
[0]=> array(2) { ["product_id"]=> int(4) ["quantity"]=> int(1) }
[1]=> array(2) { ["product_id"]=> int(10) ["quantity"]=> int(1) }
[2]=> array(2) { ["product_id"]=> int(11) ["quantity"]=> int(2) }
[3]=> array(2) { ["product_id"]=> int(11) ["quantity"]=> int(3) }
[4]=> array(2) { ["product_id"]=> int(12) ["quantity"]=> int(2) }
[5]=> array(2) { ["product_id"]=> int(12) ["quantity"]=> int(3) }
[6]=> array(2) { ["product_id"]=> int(12) ["quantity"]=> int(4) }
[7]=> array(2) { ["product_id"]=> int(12) ["quantity"]=> int(5) } }
虽然我只添加了4个产品：id 4、10、11和12
function AddToCart($pid, $q){
if(!is_array($_SESSION['products'])){
$_SESSION['products'] = array();
}
foreach($_SESSION['products'] as $key=>$my_value){
if($pid === $my_value['product_id']){
$_SESSION['products'][$key]['quantity'] += $q;
return true;
}
}
$_SESSION['products'][] = array('product_id' => $pid,
'quantity' => $q);
return true;
}