Get function is not working , passes empty to the another page - php

Question

Well i use this form of
add.php
echo " <td><form action='view_ticket.php' method='get'>
<input type='hidden' id='itemid' name='itemid' value='". $row["id"] ."'/>
<input type='submit' value='Buy' class='btn-link'/>
</form></td>";
echo "</tr>";
And i got this
view_ticket.php
<?php
session_start();
$conn = mysqli_connect("localhost", "localhost", "localhost",
"localhost");
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
$id = $_GET['itemid'];
$sql = "SELECT id,username FROM tickets WHERE id = '" . $id . "'";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
while($row = $result->fetch_assoc()) {
if ($row['username'] = $_SESSION['username']) {
}
else
{
header("location:/quickshops/buyer/tickets.php");
}
}
}
?>
the only problem i guess that $id = $_GET['itemid']; gets out empty idk how
I checked the source code of add.php , the ids in hidden area are real ,true, and numbers

Answer 1

Output $_GET at each step to see where you loose it, for instance
echo 'About to look for id "' . htmlspecialchars($id) . '"<br>';
$result = $conn->query($sql);
echo 'Just executed SQL query<br>';
var_dump($_GET); echo '<br>';
if ($result === false) {
echo 'SQL Query Error!<br>';
var_dump($_GET); echo '<br>';
} else if ($result->num_rows > 0) {
echo $result->num_rows . ' row(s) found<br>';
var_dump($_GET); echo '<br>'; /* do something */
} else {
echo 'No rows round<br>';
var_dump($_GET); echo '<br>';
}