Cannot modify header information - headers already sent by ...
количество секунд, прошедших с 1 января 1970 года 00:00:00 UTC
$time = '11:00:00';
$duration = '03:30:00';
$timeParts = explode(':', $time);
$durationParts = explode(':', $duration);
function timeSum(...$arParams) {
return str_pad(array_sum($arParams), 2, '0', STR_PAD_LEFT);
}
$newTimeParts = array_map('timeSum', $timeParts, $durationParts);
$newTime = implode(':', $newTimeParts);
echo $newTime;
$query = "
SELECT
order_id,
SUM(total) as total
FROM orders
WHERE user_id = '$user_id'
GROUP BY order_id
;"
$orders = [];
while($row = mysqli_fetch_assoc($res)) {
$orderId = $row['order_id'];
unset($row['order_id']);
$orders[$orderId]['id'] = $orderId;
$orders[$orderId]['products'][] = $row;
}
$result = mysqli_query($conDB, "SELECT COUNT(*) FROM `users`");
$idmax = mysqli_fetch_row($result)[0];
<div class="col-sm-12">
<form method="post">
<input type="number" name="idupdate" class="form-control" placeholder="Введите номер статьи для редактирования" max="<?=$idmax?>">
<input type="text" name="headerupdate" class="form-control" placeholder="Введите новое имя для выбранной статьи">
<input type="text" name="textupdate" class="form-control" placeholder="Введите новый текст для выбранной статьи"><br>
<input type="submit" name="goupdate" class="btn btn-success" value="Редактировать новость">
</form>
</div>