从while循环php中选择项目

Question

For a school project I have to make a simple webshop. To display my featured products on the hopepage I used a while loop. But now I want to add a shoppingcart. So after you pressed the button add to cart the right data has to be picked and display on another page. I will do that with cookies. So all I need is to get the right data in a variable.

I tried to use the result right away but that didn't work.

<?php
  $sql = "SELECT * FROM product WHERE featured = 1 AND nr_available > 0";
  $resultquery = $conn->query($sql);


?>

<div class="preview">
  <?php while ($result = mysqli_fetch_assoc($resultquery)) : ?>
  <div class="productpreview">
    <div class="previewheader">
      <img src="images/products/<?=$result['picture']; ?>" class="previewimg" style="max-width: 300px;">
    </div>
    <div class="description">
      <h2><?=$result['title']; ?></h2>
      <p><?=$result['description']; ?></p>
      <p>Size: <?=$result['size']; ?></p>
      <p>Price: € <?=$result['price']; ?></p>
      <button class="add" onclick="window.location.href='buy.php'">Buy</button>
      <button class="add" onclick="window.location.href='shoppingcart.php'">Add to cart</button>
    </div>
  </div>
<?php endwhile; ?>
</div>

I want to store the right data in variables which I can display on another page.

Answer 1

I have tried this:

<?php
  $sql = "SELECT * FROM product WHERE featured = 1 AND nr_available > 0";
  $resultquery = $conn->query($sql);


?>

<div class="preview">
  <?php while ($result = mysqli_fetch_assoc($resultquery)) : ?>
  <div class="productpreview">
    <div class="previewheader">
      <img src="images/products/<?=$result['picture']; ?>" class="previewimg" style="max-width: 300px;">
    </div>
    <div class="description">
      <h2><?=$result['title']; ?></h2>
      <p><?=$result['description']; ?></p>
      <p>Size: <?=$result['size']; ?></p>
      <p>Price: € <?=$result['price']; ?></p>
      <button class="add" onclick="window.location.href='buy.php'">Buy</button>
      <button class="add" onclick="window.location.href='shoppingcart.php/id=<?=$result['product_id']; ?>'">Add to cart</button>
    </div>
  </div>
<?php endwhile; ?>
</div>

and this is the page where I want to show the user his shoppingcart data.

<?php
include "core/core.php";
include "parts/head.php";
include "parts/navbar.php";
include "core/helpers.php";

if ($_SESSION['loggedIn'] == 'true') {
  echo "welkom";

  $productid = $_GET['product_id'];
  $sql = "SELECT * FROM product WHERE id = '$productid'";
  $query = $conn->query($sql);

  $result = mysqli_fetch_assoc($query);

} else {
  echo "log in ";
}

?>
<h1>Your cart</h1>
<p><?=$result['title']; ?></p>
<?php
include "parts/footer.php";
 ?>

for some reason this doesn't work. I have no errors.