Yes, as Barand pointed out you need to move the form tags out of the while loop so they also contain the submit button and from what I see they might as well go out to the body tags so there are no nesting issues with the <div> tags. Another Big issue is that you are not echoing the ID in the checkbox input. I would also remove the id=".delete-checkbox" attribute. It is not needed and as was mentioned id's needs to be unique.
Now you can't just assign the checkbox value to a variable because you are dealing with an POST array. To SEE what is being sent you can print the post like so, which will give you a good picture of what you are dealing with.
echo "<pre>";
print_r($_POST);
echo "</pre>";
Now testing looks like this.
Array
(
[delete] => MASS DELETE
[delete-product-btn] => Array
(
[0] => 3
[1] => 4
[2] => 6
[3] => 7
)
)
these array ids need to be converted into a comma separated string like 3,4,6,7 to be used in your IN() condition. Now a person could just implode this array defining the separator as a comma.
$ids = implode(',', $_POST['delete-product-btn']);
However it's a good practice to bind values being sent to a query. To do this those 3,4,6,7 values would need to be replaced with question mark placeholders. You can make an array of question marks using array_fill() which says "starting with 0 as the first KEY repeat 4 times placing a value as a question mark while making the array. But to make this dynamic we will use count($_POST['delete-product-btn']) in place of 4.
array_fill(0, count($_POST['delete-product-btn']), '?')
Which looks like this when printed.
Array
(
[5] => ?
[6] => ?
[7] => ?
[8] => ?
)
..then implode with the comma.
$placeholders = implode(',', array_fill(0, count($_POST['delete-product-btn']), '?'));
We need define the Type of values we are dealing with for each value being passed. In this case integers, which are defined as i . So we are looking for iiii, which can be made with str_repeat() again using count to defined how many i's we need.
$bindString = str_repeat("i",count($_POST['delete-product-btn']));
You can now prepare, bind and execute the query like so.
$sqlDelete = "DELETE FROM test WHERE id IN($placeholders)";
$queryDelete = $conn->prepare($sqlDelete);
$queryDelete->bind_param($bindString, ...$_POST['delete-product-btn']);
$queryDelete->execute();
If you wanted to know the number of records that were affected you could add this line right after the query.
$num = mysqli_stmt_affected_rows($queryDelete);
I would wrap all your processing code in an IF condition so it is not processed if no checkboxes are checked.
if ($_SERVER['REQUEST_METHOD'] === 'POST' && isset($_POST['delete']) && !empty($_POST['delete-product-btn'])):
$placeholders = implode(',', array_fill(0, count($_POST['delete-product-btn']), '?'));
$bindString = str_repeat("i",count($_POST['delete-product-btn']));
$sqlDelete = "DELETE FROM test WHERE id IN($placeholders)";
$queryDelete = $conn->prepare($sqlDelete);
$queryDelete->bind_param($bindString, ...$_POST['delete-product-btn']);
$queryDelete->execute();
$num = mysqli_stmt_affected_rows($queryDelete);
if(!empty($num)){
$plural = ($num !== 1 ? 's' : '');
$verb = ($num !== 1 ? 'Were' : 'Was');
echo $num.' Record'.$plural.' '.$verb.' Deleted Successfully.';
}
endif;
