Isset only checks first checkbox from database - php

Question

I have a component that gets all data from the MySQL database.
<?php
function component($productName, $productPrice, $productImg, $productID)
{
$element = "
<div class='col-md-3 col-sm-6 my-3 my-md-0'>
<form action='index.php' method='post' id='myform'>
<div class='card shadow'>
<img src='{$productImg}' alt='image1' class='img-fluid card-img-top'>
<div class=\"card-body\">
<h5 class='card-title'>{$productName}</h5>
</div>
<p class='card-text'>info goes here lorem ipsum</p>
<span class='price'>{$productPrice}</span>
<span class='price'>{$productID}</span>
<div class='form-check form-switch'>
<input class='form-check-input' type='checkbox' name='checkid[]' value='{$productID}'>
</div>
<input type='hidden' name='product_id' value='{$productID}'>
</div>
</form>
</div>
";
echo $element;
}
I also have submit button for the form.
<button type="submit" name="submit" form="myform">show selected</button>
code to get containers:
<div class="container">
<div class="row text-center py-5">
<?php
$result = $database->getData();
while ($row = mysqli_fetch_assoc($result)) {
component($row['product_name'], $row['product_price'], $row['product_image'], $row['id']);
}
?>
</div>
And PHP code to check whether container is checked and return its value (productID) when submit button is clicked.
if (isset($_POST['submit'])) {
if (!empty($_POST['checkid'])) {
foreach ($_POST['checkid'] as $value) {
echo "value : " . $value . '<br/>';
}
}
}
I have several products in the database, but it only works for first checkbox. Others don't do anything.

Answer 1

You are creating a new form element each loop.
You can change your function like
function component($productName, $productPrice, $productImg, $productID)
{
$element = "
<div class='card shadow'>
<img src='{$productImg}' alt='image1' class='img-fluid card-img-top'>
<div class=\"card-body\">
<h5 class='card-title'>{$productName}</h5>
</div>
<p class='card-text'>info goes here lorem ipsum</p>
<span class='price'>{$productPrice}</span>
<span class='price'>{$productID}</span>
<div class='form-check form-switch'>
<input class='form-check-input' type='checkbox' name='checkid[]' value='{$productID}'>
</div>
<input type='hidden' name='product_id' value='{$productID}'>
</div>
";
echo $element;
}
and code to get your components (function above) and submit button in a single form like
<div class="container">
<div class="row text-center py-5">
<div class='col-md-3 col-sm-6 my-3 my-md-0'>
<form action='index.php' method='post' id='myform'>
<?php
$result = $database->getData();
while ($row = mysqli_fetch_assoc($result)) {
component($row['product_name'], $row['product_price'], $row['product_image'], $row['id']);
}
?>
<button type="submit" name="submit" form="myform">show selected</button>
</form>
</div>
</div>