Cookies not saved from the fourth column data in mysql? - php

Question

I'm just building a simple todo-list. I built the checkboxes, which save as cookies so when next time users can see the checkboxes checked.
A part of my code:
//this code is in a table which shows checkboxes in each row.
//tasks is the query which selects all from the database
<form action="index.php" method="POST" id="checksubmit" name="checksubmit">
<?php
$i = 1;
while ($row = mysqli_fetch_array($tasks)) { ?>
<tr>
<td class="tick"><div class="custom-control custom-checkbox">
<input type="checkbox" class="custom-control-input" id="check<?php echo $row['id'];?>" name="arraycheck[]" value="<?php echo $row['id'];?>"
<?php
if ((((isset($_POST['arraycheck'])) && (in_array($row['id'], $_POST['arraycheck'])))) || (isset($_COOKIE[$row['id']]))) {
if (!isset($_COOKIE[$row['id']])) {
setcookie ($row['id'],"checked='checked'",time()+3600000);
}
}
if ((isset($_POST['button-submit'])) && (!in_array($row['id'], $_POST['arraycheck']))) {
setcookie ($row['id'],"",time()-3600);
}
echo $_COOKIE[$row['id']];
?>>
<label class="custom-control-label" for="check<?php echo $row['id'];?>"></label>
</div>
</td>
</tr>
<?php
$i++;
}
?>
The code work just fine! Checkboxes are saved by cookies.
BUT THE PROBLEM: Only the first four rows worked, from the fifth row, everything didn't worked. What a weird error!

Answer 1

There are some problems with your code:
The setcookie() calls won't work at all and will fail with a "headers already sent" warning. This is the main reason why your code is not working.
Your are using tr without having a table. If you have a table outside of the form I think this is not valid.
At least in the code you posted the form is not closed.
This line produces a "undefined offset" warning if the cookie is not set:
echo $_COOKIE[$row['id']];
You should also indent your code because then you can see mistakes better.
And if not already done add this to the beginning to see errors and warnings:
error_reporting(E_ALL | E_NOTICE);

Answer 2

The full code:
<table class="table">
<thead class="thead-dark">
<tr>
<th>STT</th>
<th>Lời nhắc</th>
<th style="width: 50px;">Xong?</th>
<th style="width: 50px;">Ảnh</th>
</tr>
</thead>
<tbody>
<form action="index.php" method="POST" id="checksubmit" name="checksubmit">
<?php $i = 1; while ($row = mysqli_fetch_array($tasks)) { ?>
<tr>
<td> <?php echo $i; ?> </td>
<td class="task"> <?php if(isset($_COOKIE[$row['id']])) {echo '<span style="color:gray;"><strike>';} echo $row['task']; if(isset($_COOKIE[$row['id']])) {echo '</strike></span>';} ?> </td>
<td class="tick"><div class="custom-control custom-checkbox">
<input type="checkbox" class="custom-control-input" id="check<?php echo $row['id'];?>" name="arraycheck[]" value="<?php echo $row['id'];?>"
<?php
if((((isset($_POST['arraycheck'])) && (in_array($row['id'], $_POST['arraycheck'])))) || (isset($_COOKIE[$row['id']]))) {
if(!isset($_COOKIE[$row['id']])) {
setcookie ($row['id'],"checked='checked'",time()+3600000); }
}
if ((isset($_POST['button-submit'])) && (!in_array($row['id'], $_POST['arraycheck']))) {
setcookie ($row['id'],"",time()-3600);
}
echo $_COOKIE[$row['id']];
?>>
<label class="custom-control-label" for="check<?php echo $row['id'];?>"></label>
</div></td>
<td><?php if (!empty($row['image'])) { ?> <i class="fas fa-image"></i> <?php } ?></td>
</tr>
<?php $i++; } ?>
<tr>
<td></td>
<td></td>
<td></td>
<td><input type="submit" value="Lưu" class="btn btn-primary" name="button-submit">
</form></td>
</tr>
</tbody>
</table>